diff --git a/components/device-mgt/org.wso2.carbon.device.mgt.api/src/main/java/org/wso2/carbon/device/mgt/jaxrs/beans/RoleWrapper.java b/components/device-mgt/org.wso2.carbon.device.mgt.api/src/main/java/org/wso2/carbon/device/mgt/jaxrs/beans/RoleInfo.java
similarity index 94%
rename from components/device-mgt/org.wso2.carbon.device.mgt.api/src/main/java/org/wso2/carbon/device/mgt/jaxrs/beans/RoleWrapper.java
rename to components/device-mgt/org.wso2.carbon.device.mgt.api/src/main/java/org/wso2/carbon/device/mgt/jaxrs/beans/RoleInfo.java
index c0856021e2..e62b5a4a3c 100644
--- a/components/device-mgt/org.wso2.carbon.device.mgt.api/src/main/java/org/wso2/carbon/device/mgt/jaxrs/beans/RoleWrapper.java
+++ b/components/device-mgt/org.wso2.carbon.device.mgt.api/src/main/java/org/wso2/carbon/device/mgt/jaxrs/beans/RoleInfo.java
@@ -22,9 +22,9 @@ import io.swagger.annotations.ApiModel;
 import io.swagger.annotations.ApiModelProperty;
 import org.wso2.carbon.user.mgt.common.UIPermissionNode;
 
-@ApiModel(value = "RoleWrapper", description = "Role details including permission and the users in the roles are " +
+@ApiModel(value = "RoleInfo", description = "Role details including permission and the users in the roles are " +
         "wrapped here.")
-public class RoleWrapper {
+public class RoleInfo {
 
     @ApiModelProperty(name = "roleName", value = "The name of the role.", required = true)
     private String roleName;
diff --git a/components/device-mgt/org.wso2.carbon.device.mgt.api/src/main/java/org/wso2/carbon/device/mgt/jaxrs/service/api/ActivityInfoProviderService.java b/components/device-mgt/org.wso2.carbon.device.mgt.api/src/main/java/org/wso2/carbon/device/mgt/jaxrs/service/api/ActivityInfoProviderService.java
index 3cdc31ed07..275a31cd07 100644
--- a/components/device-mgt/org.wso2.carbon.device.mgt.api/src/main/java/org/wso2/carbon/device/mgt/jaxrs/service/api/ActivityInfoProviderService.java
+++ b/components/device-mgt/org.wso2.carbon.device.mgt.api/src/main/java/org/wso2/carbon/device/mgt/jaxrs/service/api/ActivityInfoProviderService.java
@@ -78,7 +78,7 @@ public interface ActivityInfoProviderService {
                     response = ErrorResponse.class),
             @ApiResponse(
                     code = 401,
-                    message = ". \n Invalid request or validation error."),
+                    message = "Unauthorized. \n Unauthorized request."),
             @ApiResponse(
                     code = 404,
                     message = "Not Found. \n No activity is found under the provided id.",
@@ -88,7 +88,7 @@ public interface ActivityInfoProviderService {
                     message = "Not Acceptable.\n The requested media type is not supported"),
             @ApiResponse(
                     code = 500,
-                    message = "Internal Server ErrorResponse. \n Server error occurred while fetching activity data.",
+                    message = "Internal Server Error. \n Server error occurred while fetching activity data.",
                     response = ErrorResponse.class)
     })
     @Permission(scope = "activity-view", permissions = {"/permission/admin/device-mgt/admin/activities/view"})
@@ -135,6 +135,9 @@ public interface ActivityInfoProviderService {
                     code = 304,
                     message = "Not Modified. \n Empty body because the client has already the latest version of " +
                             "the requested resource."),
+            @ApiResponse(
+                    code = 401,
+                    message = "Unauthorized. \n Unauthorized request."),
             @ApiResponse(
                     code = 404,
                     message = "Not Found. \n No activities found.",
@@ -144,7 +147,7 @@ public interface ActivityInfoProviderService {
                     message = "Not Acceptable.\n The requested media type is not supported"),
             @ApiResponse(
                     code = 500,
-                    message = "Internal Server ErrorResponse. \n Server error occurred while fetching activity data.",
+                    message = "Internal Server Error. \n Server error occurred while fetching activity data.",
                     response = ErrorResponse.class)
     })
     @Permission(scope = "activity-view", permissions = {"/permission/admin/device-mgt/admin/activities/view"})
diff --git a/components/device-mgt/org.wso2.carbon.device.mgt.api/src/main/java/org/wso2/carbon/device/mgt/jaxrs/service/api/ConfigurationManagementService.java b/components/device-mgt/org.wso2.carbon.device.mgt.api/src/main/java/org/wso2/carbon/device/mgt/jaxrs/service/api/ConfigurationManagementService.java
index ab067e0e19..5cbe24305d 100644
--- a/components/device-mgt/org.wso2.carbon.device.mgt.api/src/main/java/org/wso2/carbon/device/mgt/jaxrs/service/api/ConfigurationManagementService.java
+++ b/components/device-mgt/org.wso2.carbon.device.mgt.api/src/main/java/org/wso2/carbon/device/mgt/jaxrs/service/api/ConfigurationManagementService.java
@@ -68,13 +68,14 @@ public interface ConfigurationManagementService {
                     }),
             @ApiResponse(
                     code = 304,
-                    message = "Not Modified. \n Empty body because the client has already the latest version of the requested resource."),
+                    message = "Not Modified. \n Empty body because the client has already the latest version of " +
+                            "the requested resource."),
             @ApiResponse(
                     code = 406,
                     message = "Not Acceptable.\n The requested media type is not supported"),
             @ApiResponse(
                     code = 500,
-                    message = "Internal Server ErrorResponse. \n Server error occurred while fetching the general " +
+                    message = "Internal Server Error. \n Server error occurred while fetching the general " +
                             "platform configuration.",
                     response = ErrorResponse.class)
     })
@@ -100,9 +101,6 @@ public interface ConfigurationManagementService {
                     code = 200,
                     message = "OK. \n General platform configuration has been updated successfully",
                     responseHeaders = {
-                            @ResponseHeader(
-                                    name = "Content-Location",
-                                    description = "URL of the updated general platform configuration."),
                             @ResponseHeader(
                                     name = "Content-Type",
                                     description = "The content type of the body"),
@@ -122,7 +120,7 @@ public interface ConfigurationManagementService {
                     message = "Unsupported media type. \n The entity of the request was in a not supported format."),
             @ApiResponse(
                     code = 500,
-                    message = "Internal Server ErrorResponse. \n " +
+                    message = "Internal Server Error. \n " +
                             "Server error occurred while modifying general platform configuration.",
                     response = ErrorResponse.class)
     })
diff --git a/components/device-mgt/org.wso2.carbon.device.mgt.api/src/main/java/org/wso2/carbon/device/mgt/jaxrs/service/api/DeviceManagementService.java b/components/device-mgt/org.wso2.carbon.device.mgt.api/src/main/java/org/wso2/carbon/device/mgt/jaxrs/service/api/DeviceManagementService.java
index a3958d4dac..7f90c9b3c0 100644
--- a/components/device-mgt/org.wso2.carbon.device.mgt.api/src/main/java/org/wso2/carbon/device/mgt/jaxrs/service/api/DeviceManagementService.java
+++ b/components/device-mgt/org.wso2.carbon.device.mgt.api/src/main/java/org/wso2/carbon/device/mgt/jaxrs/service/api/DeviceManagementService.java
@@ -87,7 +87,7 @@ public interface DeviceManagementService {
                     message = "Not Acceptable.\n The requested media type is not supported"),
             @ApiResponse(
                     code = 500,
-                    message = "Internal Server ErrorResponse. \n Server error occurred while fetching the device list.",
+                    message = "Internal Server Error. \n Server error occurred while fetching the device list.",
                     response = ErrorResponse.class)
     })
     @Permission(
@@ -193,7 +193,7 @@ public interface DeviceManagementService {
                             response = ErrorResponse.class),
                     @ApiResponse(
                             code = 500,
-                            message = "Internal Server ErrorResponse. \n " +
+                            message = "Internal Server Error. \n " +
                                     "Server error occurred while retrieving information requested device.",
                             response = ErrorResponse.class)
             })
@@ -279,7 +279,7 @@ public interface DeviceManagementService {
                             message = "Not Acceptable. \n The requested media type is not supported."),
                     @ApiResponse(
                             code = 500,
-                            message = "Internal Server ErrorResponse. \n " +
+                            message = "Internal Server Error. \n " +
                                     "Server error occurred while retrieving feature list of the device.",
                             response = ErrorResponse.class)
             })
@@ -358,7 +358,7 @@ public interface DeviceManagementService {
                             message = "Unsupported media type. \n The entity of the request was in a not supported format."),
                     @ApiResponse(
                             code = 500,
-                            message = "Internal Server ErrorResponse. \n " +
+                            message = "Internal Server Error. \n " +
                                     "Server error occurred while enrolling the device.",
                             response = ErrorResponse.class)
             })
@@ -440,9 +440,8 @@ public interface DeviceManagementService {
                             message = "Not Acceptable. \n The requested media type is not supported."),
                     @ApiResponse(
                             code = 500,
-                            message = "Internal Server ErrorResponse. \n " +
-                                    "Server error occurred while retrieving installed application list of "
-                                    + "the device.",
+                            message = "Internal Server Error. \n " +
+                                    "Server error occurred while retrieving installed application list of the device.",
                             response = ErrorResponse.class)
             })
     @Permission(
@@ -541,9 +540,8 @@ public interface DeviceManagementService {
                             message = "Not Acceptable. \n The requested media type is not supported."),
                     @ApiResponse(
                             code = 500,
-                            message = "Internal Server ErrorResponse. \n " +
-                                    "Server error occurred while retrieving operation list scheduled for the "
-                                    + "device.",
+                            message = "Internal Server Error. \n " +
+                                    "Server error occurred while retrieving operation list scheduled for the device.",
                             response = ErrorResponse.class)
             })
     @Permission(
@@ -643,9 +641,8 @@ public interface DeviceManagementService {
                             message = "Not Acceptable. \n The requested media type is not supported."),
                     @ApiResponse(
                             code = 500,
-                            message = "Internal Server ErrorResponse. \n " +
-                                    "Server error occurred while retrieving the effective policy calculated "
-                                    + "for the device.",
+                            message = "Internal Server Error. \n " +
+                                    "Server error occurred while retrieving the effective policy calculated for the device.",
                             response = ErrorResponse.class)
             }
     )
@@ -670,24 +667,4 @@ public interface DeviceManagementService {
             @HeaderParam("If-Modified-Since")
                     String ifModifiedSince);
 
-    @GET
-    @Path("/types")
-    @ApiOperation(
-            produces = MediaType.APPLICATION_JSON,
-            httpMethod = "GET",
-            value = "Get the device type.",
-            notes = "You are able to register Android, iOS and Windows devices with WSO2 EMM. In order to"
-                    + "retrieve the device type details that are registered this end-point van be used.",
-            tags = "Device Management")
-    @ApiResponses(
-            value = {
-                    @ApiResponse(
-                            code = 200,
-                            message = "OK. \n Registered device types have successfully retrieved"),
-                    @ApiResponse(
-                            code = 500,
-                            message = "Error occurred while fetching the list of device types.")
-            }
-    )
-    Response getDeviceTypes();
 }
diff --git a/components/device-mgt/org.wso2.carbon.device.mgt.api/src/main/java/org/wso2/carbon/device/mgt/jaxrs/service/api/NotificationManagementService.java b/components/device-mgt/org.wso2.carbon.device.mgt.api/src/main/java/org/wso2/carbon/device/mgt/jaxrs/service/api/NotificationManagementService.java
index de119c553e..33838ef48d 100644
--- a/components/device-mgt/org.wso2.carbon.device.mgt.api/src/main/java/org/wso2/carbon/device/mgt/jaxrs/service/api/NotificationManagementService.java
+++ b/components/device-mgt/org.wso2.carbon.device.mgt.api/src/main/java/org/wso2/carbon/device/mgt/jaxrs/service/api/NotificationManagementService.java
@@ -86,7 +86,8 @@ public interface NotificationManagementService {
                             message = "Not Acceptable.\n The requested media type is not supported"),
                     @ApiResponse(
                             code = 500,
-                            message = "Internal Server ErrorResponse. \n Server error occurred while fetching the notification list.",
+                            message = "Internal Server Error. " +
+                                    "\n Server error occurred while fetching the notification list.",
                             response = ErrorResponse.class)
             })
     @Permission(
diff --git a/components/device-mgt/org.wso2.carbon.device.mgt.api/src/main/java/org/wso2/carbon/device/mgt/jaxrs/service/api/PolicyManagementService.java b/components/device-mgt/org.wso2.carbon.device.mgt.api/src/main/java/org/wso2/carbon/device/mgt/jaxrs/service/api/PolicyManagementService.java
index 9b63bd0e47..7fde2c4233 100644
--- a/components/device-mgt/org.wso2.carbon.device.mgt.api/src/main/java/org/wso2/carbon/device/mgt/jaxrs/service/api/PolicyManagementService.java
+++ b/components/device-mgt/org.wso2.carbon.device.mgt.api/src/main/java/org/wso2/carbon/device/mgt/jaxrs/service/api/PolicyManagementService.java
@@ -90,7 +90,7 @@ public interface PolicyManagementService {
                             message = "Unsupported media type. \n The entity of the request was in a not supported format."),
                     @ApiResponse(
                             code = 500,
-                            message = "Internal Server ErrorResponse. \n " +
+                            message = "Internal Server Error. \n " +
                                     "Server error occurred while adding a new policy.",
                             response = ErrorResponse.class)
             })
@@ -145,7 +145,7 @@ public interface PolicyManagementService {
                             message = "Not Acceptable.\n The requested media type is not supported"),
                     @ApiResponse(
                             code = 500,
-                            message = ("Internal Server ErrorResponse. \n Server error occurred while fetching " +
+                            message = ("Internal Server Error. \n Server error occurred while fetching " +
                                     "policies."),
                             response = ErrorResponse.class)
             })
@@ -213,7 +213,7 @@ public interface PolicyManagementService {
                             message = "Not Acceptable.\n The requested media type is not supported"),
                     @ApiResponse(
                             code = 500,
-                            message = "Internal Server ErrorResponse. \n Server error occurred while fetching the " +
+                            message = "Internal Server Error. \n Server error occurred while fetching the " +
                                     "policy.",
                             response = ErrorResponse.class)
             })
@@ -277,7 +277,7 @@ public interface PolicyManagementService {
                             message = "Unsupported media type. \n The entity of the request was in a not supported format."),
                     @ApiResponse(
                             code = 500,
-                            message = "Internal Server ErrorResponse. \n " +
+                            message = "Internal Server Error. \n " +
                                     "Server error occurred while updating the policy.",
                             response = ErrorResponse.class)
             })
@@ -324,7 +324,7 @@ public interface PolicyManagementService {
                             message = "Unsupported media type. \n The entity of the request was in a not supported format."),
                     @ApiResponse(
                             code = 500,
-                            message = "Internal Server ErrorResponse. \n " +
+                            message = "Internal Server Error. \n " +
                                     "Server error occurred while bulk removing policies.",
                             response = ErrorResponse.class)
             })
diff --git a/components/device-mgt/org.wso2.carbon.device.mgt.api/src/main/java/org/wso2/carbon/device/mgt/jaxrs/service/api/RoleManagementService.java b/components/device-mgt/org.wso2.carbon.device.mgt.api/src/main/java/org/wso2/carbon/device/mgt/jaxrs/service/api/RoleManagementService.java
index 06f52e1dda..a42758e215 100644
--- a/components/device-mgt/org.wso2.carbon.device.mgt.api/src/main/java/org/wso2/carbon/device/mgt/jaxrs/service/api/RoleManagementService.java
+++ b/components/device-mgt/org.wso2.carbon.device.mgt.api/src/main/java/org/wso2/carbon/device/mgt/jaxrs/service/api/RoleManagementService.java
@@ -21,10 +21,9 @@ package org.wso2.carbon.device.mgt.jaxrs.service.api;
 import io.swagger.annotations.*;
 import org.wso2.carbon.apimgt.annotations.api.API;
 import org.wso2.carbon.apimgt.annotations.api.Permission;
-import org.wso2.carbon.device.mgt.common.configuration.mgt.PlatformConfiguration;
 import org.wso2.carbon.device.mgt.jaxrs.beans.ErrorResponse;
+import org.wso2.carbon.device.mgt.jaxrs.beans.RoleInfo;
 import org.wso2.carbon.device.mgt.jaxrs.beans.RoleList;
-import org.wso2.carbon.device.mgt.jaxrs.beans.RoleWrapper;
 import org.wso2.carbon.user.mgt.common.UIPermissionNode;
 
 import javax.ws.rs.*;
@@ -70,16 +69,12 @@ public interface RoleManagementService {
                     @ApiResponse(
                             code = 304,
                             message = "Not Modified. \n Empty body because the client has already the latest version of the requested resource."),
-                    @ApiResponse(
-                            code = 404,
-                            message = "Not Found. \n Resource does not exist.",
-                            response = ErrorResponse.class),
                     @ApiResponse(
                             code = 406,
                             message = "Not Acceptable.\n The requested media type is not supported"),
                     @ApiResponse(
                             code = 500,
-                            message = "Internal Server ErrorResponse. \n Server error occurred while fetching requested list of roles.",
+                            message = "Internal Server Error. \n Server error occurred while fetching requested list of roles.",
                             response = ErrorResponse.class)
             })
     @Permission(scope = "roles-view", permissions = {
@@ -157,11 +152,12 @@ public interface RoleManagementService {
                             response = ErrorResponse.class),
                     @ApiResponse(
                             code = 404,
-                            message = "Not Found. \n Resource does not exist.",
+                            message = "Not Found. \n Role does not exist.",
                             response = ErrorResponse.class),
                     @ApiResponse(
                             code = 406,
-                            message = "Not Acceptable.\n The requested media type is not supported"),
+                            message = "Not Acceptable.\n The requested media type is not supported",
+                            response = ErrorResponse.class),
                     @ApiResponse(
                             code = 500,
                             message = "Internal Server ErrorResponse. \n Server error occurred while fetching the permission list of the requested role.",
@@ -187,14 +183,14 @@ public interface RoleManagementService {
             httpMethod = "GET",
             value = "Get details of a role.",
             notes = "If you wish to get the details of a role in  EMM, you can do so using this REST API.",
-            response = RoleWrapper.class,
+            response = RoleInfo.class,
             tags = "Role Management")
     @ApiResponses(
             value = {
                     @ApiResponse(
                             code = 200,
                             message = "OK. \n Successfully fetched the requested role.",
-                            response = RoleWrapper.class,
+                            response = RoleInfo.class,
                             responseHeaders = {
                                     @ResponseHeader(
                                             name = "Content-Type",
@@ -218,14 +214,15 @@ public interface RoleManagementService {
                             response = ErrorResponse.class),
                     @ApiResponse(
                             code = 404,
-                            message = "Not Found. \n Resource does not exist.",
+                            message = "Not Found. \n Role does not exist.",
                             response = ErrorResponse.class),
                     @ApiResponse(
                             code = 406,
-                            message = "Not Acceptable.\n The requested media type is not supported"),
+                            message = "Not Acceptable.\n The requested media type is not supported",
+                            response = ErrorResponse.class),
                     @ApiResponse(
                             code = 500,
-                            message = "Internal Server ErrorResponse. \n Server error occurred while fetching the " +
+                            message = "Internal Server Error. \n Server error occurred while fetching the " +
                                     "requested role.",
                             response = ErrorResponse.class)
     })
@@ -282,11 +279,11 @@ public interface RoleManagementService {
                     response = ErrorResponse.class),
             @ApiResponse(
                     code = 415,
-                    message = "Unsupported media type. \n The entity of the request was in a not supported format."),
+                    message = "Unsupported media type. \n The entity of the request was in a not supported format.",
+                    response = ErrorResponse.class),
             @ApiResponse(
                     code = 500,
-                    message = "Internal Server ErrorResponse. \n " +
-                            "Server error occurred while adding a new role.",
+                    message = "Internal Server Error. \n Server error occurred while adding a new role.",
                     response = ErrorResponse.class)
     })
     @Permission(scope = "roles-modify", permissions = {"/permission/admin/device-mgt/admin/roles/add"})
@@ -294,7 +291,7 @@ public interface RoleManagementService {
             @ApiParam(
                     name = "role",
                     value = "Details about the role to be added.",
-                    required = true) RoleWrapper role);
+                    required = true) RoleInfo role);
 
     @PUT
     @Path("/{roleName}")
@@ -311,9 +308,6 @@ public interface RoleManagementService {
                     code = 200,
                     message = "OK. \n Role has been updated successfully",
                     responseHeaders = {
-                            @ResponseHeader(
-                                    name = "Content-Location",
-                                    description = "URL of the updated role."),
                             @ResponseHeader(
                                     name = "Content-Type",
                                     description = "Content type of the body"),
@@ -331,14 +325,15 @@ public interface RoleManagementService {
                     response = ErrorResponse.class),
             @ApiResponse(
                     code = 404,
-                    message = "Not Found. \n Resource to be deleted does not exist."),
+                    message = "Not Found. \n Role to be deleted does not exist.",
+                    response = ErrorResponse.class),
             @ApiResponse(
                     code = 415,
-                    message = "Unsupported media type. \n The entity of the request was in a not supported format."),
+                    message = "Unsupported media type. \n The entity of the request was in a not supported format.",
+                    response = ErrorResponse.class),
             @ApiResponse(
                     code = 500,
-                    message = "Internal Server ErrorResponse. \n " +
-                            "Server error occurred while updating the role.",
+                    message = "Internal Server Error. \n Server error occurred while updating the role.",
                     response = ErrorResponse.class)
     })
     @Permission(scope = "roles-modify", permissions = {"/permission/admin/device-mgt/admin/roles/update"})
@@ -351,7 +346,7 @@ public interface RoleManagementService {
             @ApiParam(
                     name = "role",
                     value = "Details about the role to be added.",
-                    required = true) RoleWrapper role);
+                    required = true) RoleInfo role);
 
     @DELETE
     @Path("/{roleName}")
@@ -371,11 +366,11 @@ public interface RoleManagementService {
                     response = ErrorResponse.class),
             @ApiResponse(
                     code = 404,
-                    message = "Not Found. \n Resource to be deleted does not exist."),
+                    message = "Not Found. \n Role to be deleted does not exist.",
+                    response = ErrorResponse.class),
             @ApiResponse(
                     code = 500,
-                    message = "Internal Server ErrorResponse. \n " +
-                            "Server error occurred while removing the role.",
+                    message = "Internal Server Error. \n Server error occurred while removing the role.",
                     response = ErrorResponse.class)
     })
     @Permission(scope = "roles-modify", permissions = {"/permission/admin/device-mgt/admin/roles/remove"})
@@ -406,9 +401,6 @@ public interface RoleManagementService {
                             code = 200,
                             message = "OK. \n User list of the role has been updated successfully",
                             responseHeaders = {
-                                    @ResponseHeader(
-                                            name = "Content-Location",
-                                            description = "URL of the updated user list."),
                                     @ResponseHeader(
                                             name = "Content-Type",
                                             description = "Content type of the body"),
@@ -426,13 +418,16 @@ public interface RoleManagementService {
                             response = ErrorResponse.class),
                     @ApiResponse(
                             code = 404,
-                            message = "Not Found. \n Resource to be deleted does not exist."),
+                            message = "Not Found. \n Resource to be deleted does not exist.",
+                            response = ErrorResponse.class),
                     @ApiResponse(
                             code = 415,
-                            message = "Unsupported media type. \n The entity of the request was in a not supported format."),
+                            message = "Unsupported media type. \n The entity of the request was in a not " +
+                                    "supported format.",
+                            response = ErrorResponse.class),
                     @ApiResponse(
                             code = 500,
-                            message = "Internal Server ErrorResponse. \n " +
+                            message = "Internal Server Error. \n " +
                                     "Server error occurred while updating the user list of the role.",
                             response = ErrorResponse.class)
     })
diff --git a/components/device-mgt/org.wso2.carbon.device.mgt.api/src/main/java/org/wso2/carbon/device/mgt/jaxrs/service/api/UserManagementService.java b/components/device-mgt/org.wso2.carbon.device.mgt.api/src/main/java/org/wso2/carbon/device/mgt/jaxrs/service/api/UserManagementService.java
index fbbeb51736..781cce69a9 100644
--- a/components/device-mgt/org.wso2.carbon.device.mgt.api/src/main/java/org/wso2/carbon/device/mgt/jaxrs/service/api/UserManagementService.java
+++ b/components/device-mgt/org.wso2.carbon.device.mgt.api/src/main/java/org/wso2/carbon/device/mgt/jaxrs/service/api/UserManagementService.java
@@ -64,34 +64,29 @@ public interface UserManagementService {
                                             name = "Last-Modified",
                                             description = "Date and time the resource has been modified the last time.\n" +
                                                     "Used by caches, or in conditional requests.")}),
-                    @ApiResponse(
-                            code = 303,
-                            message = "See Other. \n Source can be retrieved from the URL specified at the Location header.",
-                            responseHeaders = {
-                                    @ResponseHeader(
-                                            name = "Content-Location",
-                                            description = "The Source URL of the document.")}),
                     @ApiResponse(
                             code = 400,
-                            message = "Bad Request. \n Invalid request or validation error."),
+                            message = "Bad Request. \n Invalid request or validation error.",
+                            response = ErrorResponse.class),
                     @ApiResponse(
                             code = 409,
-                            message = "Conflict. \n User already exist.",
+                            message = "Conflict. \n User already exists.",
                             response = ErrorResponse.class),
                     @ApiResponse(
                             code = 415,
-                            message = "Unsupported media type. \n The entity of the request was in a not supported format."),
+                            message = "Unsupported media type. \n The entity of the request was in a not " +
+                                    "supported format.",
+                            response = ErrorResponse.class),
                     @ApiResponse(
                             code = 500,
-                            message = "Internal Server ErrorResponse. \n " +
-                                    "Server error occurred while adding a new user.",
+                            message = "Internal Server Error. \n Server error occurred while adding a new user.",
                             response = ErrorResponse.class)
             })
     @Permission(scope = "user-modify", permissions = {"/permission/admin/device-mgt/admin/user/add"})
     Response addUser(
             @ApiParam(
                     name = "user",
-                    value = "User related details.",
+                    value = "Information of the user to be added",
                     required = true) UserInfo user);
 
     @GET
@@ -131,7 +126,8 @@ public interface UserManagementService {
                     response = ErrorResponse.class),
             @ApiResponse(
                     code = 406,
-                    message = "Not Acceptable.\n The requested media type is not supported"),
+                    message = "Not Acceptable.\n The requested media type is not supported",
+                    response = ErrorResponse.class),
             @ApiResponse(
                     code = 500,
                     message = "Internal Server ErrorResponse. \n Server error occurred while" +
@@ -166,9 +162,6 @@ public interface UserManagementService {
                     code = 200,
                     message = "OK. \n User has been updated successfully",
                     responseHeaders = {
-                            @ResponseHeader(
-                                    name = "Content-Location",
-                                    description = "URL of the updated user."),
                             @ResponseHeader(
                                     name = "Content-Type",
                                     description = "Content type of the body"),
@@ -182,17 +175,19 @@ public interface UserManagementService {
                                             "Used by caches, or in conditional requests.")}),
             @ApiResponse(
                     code = 400,
-                    message = "Bad Request. \n Invalid request or validation error."),
+                    message = "Bad Request. \n Invalid request or validation error.",
+                    response = ErrorResponse.class),
             @ApiResponse(
                     code = 404,
                     message = "Not Found. \n Resource does not exist.",
                     response = ErrorResponse.class),
             @ApiResponse(
                     code = 415,
-                    message = "Unsupported media type. \n The entity of the request was in a not supported format."),
+                    message = "Unsupported media type. \n The entity of the request was in a not supported format.",
+                    response = ErrorResponse.class),
             @ApiResponse(
                     code = 500,
-                    message = "Internal Server ErrorResponse. \n " +
+                    message = "Internal Server Error. \n " +
                             "Server error occurred while updating the user.",
                     response = ErrorResponse.class)
     })
@@ -226,7 +221,7 @@ public interface UserManagementService {
                     response = ErrorResponse.class),
             @ApiResponse(
                     code = 500,
-                    message = "Internal Server ErrorResponse. \n " +
+                    message = "Internal Server Error. \n " +
                             "Server error occurred while removing the user.",
                     response = ErrorResponse.class
             )
@@ -272,10 +267,11 @@ public interface UserManagementService {
                     response = ErrorResponse.class),
             @ApiResponse(
                     code = 406,
-                    message = "Not Acceptable.\n The requested media type is not supported"),
+                    message = "Not Acceptable.\n The requested media type is not supported",
+                    response = ErrorResponse.class),
             @ApiResponse(
                     code = 500,
-                    message = "Internal Server ErrorResponse. \n Server error occurred while fetching the role list" +
+                    message = "Internal Server Error. \n Server error occurred while fetching the role list" +
                             " assigned to the user.",
                     response = ErrorResponse.class)
     })
@@ -296,7 +292,7 @@ public interface UserManagementService {
             @ApiResponse(
                     code = 200,
                     message = "OK. \n Successfully fetched the requested role.",
-                    response = UserInfoList.class,
+                    response = BasicUserInfoList.class,
                     responseHeaders = {
                             @ResponseHeader(
                                     name = "Content-Type",
@@ -315,10 +311,11 @@ public interface UserManagementService {
                     message = "Not Modified. \n Empty body because the client already has the latest version of the requested resource."),
             @ApiResponse(
                     code = 406,
-                    message = "Not Acceptable.\n The requested media type is not supported"),
+                    message = "Not Acceptable.\n The requested media type is not supported",
+                    response = ErrorResponse.class),
             @ApiResponse(
                     code = 500,
-                    message = "Internal Server ErrorResponse. \n Server error occurred while fetching the user list.",
+                    message = "Internal Server Error. \n Server error occurred while fetching the user list.",
                     response = ErrorResponse.class)
     })
     @Permission(scope = "user-view", permissions = {"/permission/admin/device-mgt/admin/user/list"})
@@ -380,10 +377,11 @@ public interface UserManagementService {
                     message = "Not Modified. \n Empty body because the client has already the latest version of the requested resource."),
             @ApiResponse(
                     code = 406,
-                    message = "Not Acceptable.\n The requested media type is not supported"),
+                    message = "Not Acceptable.\n The requested media type is not supported",
+                    response = ErrorResponse.class),
             @ApiResponse(
                     code = 500,
-                    message = "Internal Server ErrorResponse. \n Server error occurred while fetching the username " +
+                    message = "Internal Server Error. \n Server error occurred while fetching the username " +
                             "list that matches the given filter.",
                     response = ErrorResponse.class)
     })
@@ -429,13 +427,15 @@ public interface UserManagementService {
                     response = ErrorResponse.class),
             @ApiResponse(
                     code = 404,
-                    message = "Not Found. \n Resource to be deleted does not exist."),
+                    message = "Not Found. \n Resource to be deleted does not exist.",
+                    response = ErrorResponse.class),
             @ApiResponse(
                     code = 415,
-                    message = "Unsupported media type. \n The entity of the request was in a not supported format."),
+                    message = "Unsupported media type. \n The entity of the request was in a not supported format.",
+                    response = ErrorResponse.class),
             @ApiResponse(
                     code = 500,
-                    message = "Internal Server ErrorResponse. \n " +
+                    message = "Internal Server Error. \n " +
                             "Server error occurred while updating credentials of the user.",
                     response = ErrorResponse.class)
     })
diff --git a/components/device-mgt/org.wso2.carbon.device.mgt.api/src/main/java/org/wso2/carbon/device/mgt/jaxrs/service/api/admin/ApplicationManagementAdminService.java b/components/device-mgt/org.wso2.carbon.device.mgt.api/src/main/java/org/wso2/carbon/device/mgt/jaxrs/service/api/admin/ApplicationManagementAdminService.java
index 23b6cba5ab..49f15dccb1 100644
--- a/components/device-mgt/org.wso2.carbon.device.mgt.api/src/main/java/org/wso2/carbon/device/mgt/jaxrs/service/api/admin/ApplicationManagementAdminService.java
+++ b/components/device-mgt/org.wso2.carbon.device.mgt.api/src/main/java/org/wso2/carbon/device/mgt/jaxrs/service/api/admin/ApplicationManagementAdminService.java
@@ -68,7 +68,7 @@ public interface ApplicationManagementAdminService {
                     message = "Unsupported media type. \n The entity of the request was in a not supported format."),
             @ApiResponse(
                     code = 500,
-                    message = "Internal Server ErrorResponse. \n " +
+                    message = "Internal Server Error. \n " +
                             "Server error occurred while bulk issuing application installation operations upon " +
                             "a given set of devices.",
                     response = ErrorResponse.class)
@@ -106,7 +106,7 @@ public interface ApplicationManagementAdminService {
                     message = "Unsupported media type. \n The entity of the request was in a not supported format."),
             @ApiResponse(
                     code = 500,
-                    message = "Internal Server ErrorResponse. \n " +
+                    message = "Internal Server Error. \n " +
                             "Server error occurred while bulk issuing application un-installation operations upon " +
                             "a given set of devices.",
                     response = ErrorResponse.class)
diff --git a/components/device-mgt/org.wso2.carbon.device.mgt.api/src/main/java/org/wso2/carbon/device/mgt/jaxrs/service/api/admin/DeviceManagementAdminService.java b/components/device-mgt/org.wso2.carbon.device.mgt.api/src/main/java/org/wso2/carbon/device/mgt/jaxrs/service/api/admin/DeviceManagementAdminService.java
index 2396de53f1..89b8d9185b 100644
--- a/components/device-mgt/org.wso2.carbon.device.mgt.api/src/main/java/org/wso2/carbon/device/mgt/jaxrs/service/api/admin/DeviceManagementAdminService.java
+++ b/components/device-mgt/org.wso2.carbon.device.mgt.api/src/main/java/org/wso2/carbon/device/mgt/jaxrs/service/api/admin/DeviceManagementAdminService.java
@@ -80,7 +80,7 @@ public interface DeviceManagementAdminService {
                     message = "Not Acceptable.\n The requested media type is not supported"),
             @ApiResponse(
                     code = 500,
-                    message = "Internal Server ErrorResponse. \n Server error occurred while fetching the device list.",
+                    message = "Internal Server Error. \n Server error occurred while fetching the device list.",
                     response = ErrorResponse.class)
     })
     Response getDevicesByName(
diff --git a/components/device-mgt/org.wso2.carbon.device.mgt.api/src/main/java/org/wso2/carbon/device/mgt/jaxrs/service/api/admin/UserManagementAdminService.java b/components/device-mgt/org.wso2.carbon.device.mgt.api/src/main/java/org/wso2/carbon/device/mgt/jaxrs/service/api/admin/UserManagementAdminService.java
index fb8610ce43..66ca21d1fc 100644
--- a/components/device-mgt/org.wso2.carbon.device.mgt.api/src/main/java/org/wso2/carbon/device/mgt/jaxrs/service/api/admin/UserManagementAdminService.java
+++ b/components/device-mgt/org.wso2.carbon.device.mgt.api/src/main/java/org/wso2/carbon/device/mgt/jaxrs/service/api/admin/UserManagementAdminService.java
@@ -60,7 +60,7 @@ public interface UserManagementAdminService {
                     message = "Unsupported media type. \n The entity of the request was in a not supported format."),
             @ApiResponse(
                     code = 500,
-                    message = "Internal Server ErrorResponse. \n " +
+                    message = "Internal Server Error. \n " +
                             "Server error occurred while updating credentials of the user.",
                     response = ErrorResponse.class)
     })
diff --git a/components/device-mgt/org.wso2.carbon.device.mgt.api/src/main/java/org/wso2/carbon/device/mgt/jaxrs/service/impl/ActivityProviderServiceImpl.java b/components/device-mgt/org.wso2.carbon.device.mgt.api/src/main/java/org/wso2/carbon/device/mgt/jaxrs/service/impl/ActivityProviderServiceImpl.java
index 848b0749a7..444854e1e4 100644
--- a/components/device-mgt/org.wso2.carbon.device.mgt.api/src/main/java/org/wso2/carbon/device/mgt/jaxrs/service/impl/ActivityProviderServiceImpl.java
+++ b/components/device-mgt/org.wso2.carbon.device.mgt.api/src/main/java/org/wso2/carbon/device/mgt/jaxrs/service/impl/ActivityProviderServiceImpl.java
@@ -26,8 +26,7 @@ import org.wso2.carbon.device.mgt.core.service.DeviceManagementProviderService;
 import org.wso2.carbon.device.mgt.jaxrs.beans.ActivityList;
 import org.wso2.carbon.device.mgt.jaxrs.beans.ErrorResponse;
 import org.wso2.carbon.device.mgt.jaxrs.service.api.ActivityInfoProviderService;
-import org.wso2.carbon.device.mgt.jaxrs.service.impl.util.*;
-import org.wso2.carbon.device.mgt.jaxrs.service.impl.util.NotFoundException;
+import org.wso2.carbon.device.mgt.jaxrs.service.impl.util.RequestValidationUtil;
 import org.wso2.carbon.device.mgt.jaxrs.util.DeviceMgtAPIUtils;
 
 import javax.ws.rs.*;
@@ -58,17 +57,17 @@ public class ActivityProviderServiceImpl implements ActivityInfoProviderService
             dmService = DeviceMgtAPIUtils.getDeviceManagementService();
             activity = dmService.getOperationByActivityId(id);
             if (activity == null) {
-                throw new NotFoundException(new ErrorResponse.ErrorResponseBuilder().setCode(404l)
-                        .setMessage("No activity can be " +
-                                "found upon the provided activity id '" + id + "'").build());
+                return Response.status(404).entity(
+                        new ErrorResponse.ErrorResponseBuilder().setMessage("No activity can be " +
+                                "found upon the provided activity id '" + id + "'").build()).build();
             }
+            return Response.status(Response.Status.OK).entity(activity).build();
         } catch (OperationManagementException e) {
             String msg = "ErrorResponse occurred while fetching the activity for the supplied id.";
             log.error(msg, e);
-            throw new UnexpectedServerErrorException(new ErrorResponse.ErrorResponseBuilder().setCode(500l)
-                    .setMessage(msg).build());
+            return Response.serverError().entity(
+                    new ErrorResponse.ErrorResponseBuilder().setMessage(msg).build()).build();
         }
-        return Response.status(Response.Status.OK).entity(activity).build();
     }
 
     @GET
@@ -77,19 +76,21 @@ public class ActivityProviderServiceImpl implements ActivityInfoProviderService
                                   @QueryParam("limit") int limit,
                                   @HeaderParam("If-Modified-Since") String ifModifiedSince) {
 
-        long ifModifiedSinceTimestamp = 0;
-        long sinceTimestamp = 0;
+        long ifModifiedSinceTimestamp;
+        long sinceTimestamp;
         long timestamp = 0;
         boolean isIfModifiedSinceSet = false;
         boolean isSinceSet = false;
+
         if (ifModifiedSince != null && !ifModifiedSince.isEmpty()) {
             Date ifSinceDate;
             SimpleDateFormat format = new SimpleDateFormat("EEE, d MMM yyyy HH:mm:ss Z");
             try {
                 ifSinceDate = format.parse(ifModifiedSince);
             } catch (ParseException e) {
-                throw new InputValidationException(new ErrorResponse.ErrorResponseBuilder().setCode(400l)
-                        .setMessage("Invalid date string is provided in 'If-Modified-Since' header").build());
+                return Response.status(400).entity(
+                        new ErrorResponse.ErrorResponseBuilder().setMessage(
+                                "Invalid date string is provided in 'If-Modified-Since' header").build()).build();
             }
             ifModifiedSinceTimestamp = ifSinceDate.getTime();
             isIfModifiedSinceSet = true;
@@ -100,13 +101,15 @@ public class ActivityProviderServiceImpl implements ActivityInfoProviderService
             try {
                 sinceDate = format.parse(since);
             } catch (ParseException e) {
-                throw new InputValidationException(new ErrorResponse.ErrorResponseBuilder().setCode(400l)
-                        .setMessage("Invalid date string is provided in 'since' filter").build());
+                return Response.status(400).entity(
+                        new ErrorResponse.ErrorResponseBuilder().setMessage(
+                                "Invalid date string is provided in 'since' filter").build()).build();
             }
             sinceTimestamp = sinceDate.getTime();
             isSinceSet = true;
             timestamp = sinceTimestamp / 1000;
         }
+
         List<Activity> activities;
         ActivityList activityList = new ActivityList();
         DeviceManagementProviderService dmService;
@@ -117,24 +120,18 @@ public class ActivityProviderServiceImpl implements ActivityInfoProviderService
             int count = dmService.getActivityCountUpdatedAfter(timestamp);
             activityList.setCount(count);
             if (activities == null || activities.size() == 0) {
-                if (isIfModifiedSinceSet) {
-                    return Response.status(Response.Status.NOT_MODIFIED).entity(
-                            "No activities " + "after the time provided in 'If-Modified-Since' header")
-                            .build();
-                } else if (isSinceSet) {
-                    return Response.status(Response.Status.NOT_MODIFIED).entity(
-                            "No activities " + "after the time provided in 'since' filter").build();
+                if (isIfModifiedSinceSet || isSinceSet) {
+                    return Response.notModified().build();
                 }
-                throw new NotFoundException(new ErrorResponse.ErrorResponseBuilder().setCode(404l)
-                        .setMessage("No activities " + "found.").build());
             }
+            return Response.ok().entity(activityList).build();
         } catch (OperationManagementException e) {
             String msg
                     = "ErrorResponse occurred while fetching the activities updated after given time stamp.";
             log.error(msg, e);
-            throw new UnexpectedServerErrorException(new ErrorResponse.ErrorResponseBuilder().setCode(500l)
-                    .setMessage(msg).build());
+            return Response.serverError().entity(
+                    new ErrorResponse.ErrorResponseBuilder().setMessage(msg).build()).build();
         }
-        return Response.status(Response.Status.OK).entity(activityList).build();
     }
+
 }
diff --git a/components/device-mgt/org.wso2.carbon.device.mgt.api/src/main/java/org/wso2/carbon/device/mgt/jaxrs/service/impl/ConfigurationServiceImpl.java b/components/device-mgt/org.wso2.carbon.device.mgt.api/src/main/java/org/wso2/carbon/device/mgt/jaxrs/service/impl/ConfigurationServiceImpl.java
index c10e82e762..0c082722fd 100644
--- a/components/device-mgt/org.wso2.carbon.device.mgt.api/src/main/java/org/wso2/carbon/device/mgt/jaxrs/service/impl/ConfigurationServiceImpl.java
+++ b/components/device-mgt/org.wso2.carbon.device.mgt.api/src/main/java/org/wso2/carbon/device/mgt/jaxrs/service/impl/ConfigurationServiceImpl.java
@@ -55,19 +55,19 @@ public class ConfigurationServiceImpl implements ConfigurationManagementService
             ConfigurationEntry configurationEntry = new ConfigurationEntry();
             configurationEntry.setContentType("text");
             configurationEntry.setName("notifierFrequency");
-            configurationEntry.setValue(PolicyManagerUtil.getMonitoringFequency());
+            configurationEntry.setValue(PolicyManagerUtil.getMonitoringFrequency());
             List<ConfigurationEntry> configList = config.getConfiguration();
             if (configList == null) {
                 configList = new ArrayList<>();
                 configList.add(configurationEntry);
             }
             config.setConfiguration(configList);
-            return Response.status(Response.Status.OK).entity(config).build();
+            return Response.ok().entity(config).build();
         } catch (ConfigurationManagementException | PolicyManagementException e) {
-            msg = "ErrorResponse occurred while retrieving the configurations.";
+            msg = "Error occurred while retrieving the general platform configuration";
             log.error(msg, e);
-            throw new UnexpectedServerErrorException(
-                    new ErrorResponse.ErrorResponseBuilder().setCode(500l).setMessage(msg).build());
+            return Response.serverError().entity(
+                    new ErrorResponse.ErrorResponseBuilder().setMessage(msg).build()).build();
         }
     }
 
@@ -80,13 +80,15 @@ public class ConfigurationServiceImpl implements ConfigurationManagementService
                     MDMAppConstants.RegistryConstants.GENERAL_CONFIG_RESOURCE_PATH);
             //Schedule the task service
             DeviceMgtAPIUtils.scheduleTaskService(DeviceMgtAPIUtils.getNotifierFrequency(config));
-            return Response.status(Response.Status.CREATED)
-                    .entity("Configuration has successfully been updated").build();
+
+            PlatformConfiguration updatedConfig = DeviceMgtAPIUtils.getPlatformConfigurationManagementService().
+                    getConfiguration(MDMAppConstants.RegistryConstants.GENERAL_CONFIG_RESOURCE_PATH);
+            return Response.ok().entity(updatedConfig).build();
         } catch (ConfigurationManagementException e) {
-            String msg = "ErrorResponse occurred while updating the configuration.";
+            String msg = "Error occurred while updating the general platform configuration";
             log.error(msg, e);
-            throw new UnexpectedServerErrorException(
-                    new ErrorResponse.ErrorResponseBuilder().setCode(500l).setMessage(msg).build());
+            return Response.serverError().entity(
+                    new ErrorResponse.ErrorResponseBuilder().setMessage(msg).build()).build();
         }
     }
 
diff --git a/components/device-mgt/org.wso2.carbon.device.mgt.api/src/main/java/org/wso2/carbon/device/mgt/jaxrs/service/impl/DeviceManagementServiceImpl.java b/components/device-mgt/org.wso2.carbon.device.mgt.api/src/main/java/org/wso2/carbon/device/mgt/jaxrs/service/impl/DeviceManagementServiceImpl.java
index 62dca8864c..edac09a140 100644
--- a/components/device-mgt/org.wso2.carbon.device.mgt.api/src/main/java/org/wso2/carbon/device/mgt/jaxrs/service/impl/DeviceManagementServiceImpl.java
+++ b/components/device-mgt/org.wso2.carbon.device.mgt.api/src/main/java/org/wso2/carbon/device/mgt/jaxrs/service/impl/DeviceManagementServiceImpl.java
@@ -27,7 +27,6 @@ import org.wso2.carbon.device.mgt.common.operation.mgt.Operation;
 import org.wso2.carbon.device.mgt.common.operation.mgt.OperationManagementException;
 import org.wso2.carbon.device.mgt.common.search.SearchContext;
 import org.wso2.carbon.device.mgt.core.app.mgt.ApplicationManagementProviderService;
-import org.wso2.carbon.device.mgt.core.dto.DeviceType;
 import org.wso2.carbon.device.mgt.core.search.mgt.SearchManagerService;
 import org.wso2.carbon.device.mgt.core.search.mgt.SearchMgtException;
 import org.wso2.carbon.device.mgt.core.service.DeviceManagementProviderService;
@@ -35,10 +34,7 @@ import org.wso2.carbon.device.mgt.jaxrs.beans.DeviceList;
 import org.wso2.carbon.device.mgt.jaxrs.beans.ErrorResponse;
 import org.wso2.carbon.device.mgt.jaxrs.beans.OperationList;
 import org.wso2.carbon.device.mgt.jaxrs.service.api.DeviceManagementService;
-import org.wso2.carbon.device.mgt.jaxrs.service.impl.util.InputValidationException;
-import org.wso2.carbon.device.mgt.jaxrs.service.impl.util.NotFoundException;
 import org.wso2.carbon.device.mgt.jaxrs.service.impl.util.RequestValidationUtil;
-import org.wso2.carbon.device.mgt.jaxrs.service.impl.util.UnexpectedServerErrorException;
 import org.wso2.carbon.device.mgt.jaxrs.util.DeviceMgtAPIUtils;
 import org.wso2.carbon.policy.mgt.common.Policy;
 import org.wso2.carbon.policy.mgt.common.PolicyManagementException;
@@ -100,9 +96,9 @@ public class DeviceManagementServiceImpl implements DeviceManagementService {
                 try {
                     sinceDate = format.parse(ifModifiedSince);
                 } catch (ParseException e) {
-                    throw new InputValidationException(
-                            new ErrorResponse.ErrorResponseBuilder().setCode(400l).setMessage("Invalid date " +
-                                    "string is provided in 'If-Modified-Since' header").build());
+                    return Response.status(Response.Status.BAD_REQUEST).entity(
+                            new ErrorResponse.ErrorResponseBuilder().setMessage("Invalid date " +
+                                    "string is provided in 'If-Modified-Since' header").build()).build();
                 }
                 request.setSince(sinceDate);
                 result = dms.getAllDevices(request);
@@ -116,9 +112,9 @@ public class DeviceManagementServiceImpl implements DeviceManagementService {
                 try {
                     sinceDate = format.parse(since);
                 } catch (ParseException e) {
-                    throw new InputValidationException(
-                            new ErrorResponse.ErrorResponseBuilder().setCode(400l).setMessage("Invalid date " +
-                                    "string is provided in 'since' filter").build());
+                    return Response.status(Response.Status.BAD_REQUEST).entity(
+                            new ErrorResponse.ErrorResponseBuilder().setMessage("Invalid date " +
+                                    "string is provided in 'since' filter").build()).build();
                 }
                 request.setSince(sinceDate);
                 result = dms.getAllDevices(request);
@@ -140,8 +136,8 @@ public class DeviceManagementServiceImpl implements DeviceManagementService {
         } catch (DeviceManagementException e) {
             String msg = "Error occurred while fetching all enrolled devices";
             log.error(msg, e);
-            throw new UnexpectedServerErrorException(
-                    new ErrorResponse.ErrorResponseBuilder().setCode(500l).setMessage(msg).build());
+            return Response.serverError().entity(
+                    new ErrorResponse.ErrorResponseBuilder().setMessage(msg).build()).build();
         }
     }
 
@@ -161,13 +157,13 @@ public class DeviceManagementServiceImpl implements DeviceManagementService {
         } catch (DeviceManagementException e) {
             String msg = "Error occurred while fetching the device information.";
             log.error(msg, e);
-            throw new UnexpectedServerErrorException(
-                    new ErrorResponse.ErrorResponseBuilder().setCode(500l).setMessage(msg).build());
+            return Response.serverError().entity(
+                    new ErrorResponse.ErrorResponseBuilder().setMessage(msg).build()).build();
         }
         if (device == null) {
-            throw new NotFoundException(
+            return Response.status(Response.Status.NOT_FOUND).entity(
                     new ErrorResponse.ErrorResponseBuilder().setCode(404l).setMessage("Requested device of type '" +
-                            type + "', which carries id '" + id + "' does not exist").build());
+                            type + "', which carries id '" + id + "' does not exist").build()).build();
         }
         return Response.status(Response.Status.OK).entity(device).build();
     }
@@ -187,17 +183,17 @@ public class DeviceManagementServiceImpl implements DeviceManagementService {
             dms = DeviceMgtAPIUtils.getDeviceManagementService();
             FeatureManager fm = dms.getFeatureManager(type);
             if (fm == null) {
-                throw new NotFoundException(
-                        new ErrorResponse.ErrorResponseBuilder().setCode(404l).setMessage("No feature manager is " +
-                                "registered with the given type '" + type + "'").build());
+                return Response.status(Response.Status.NOT_FOUND).entity(
+                        new ErrorResponse.ErrorResponseBuilder().setMessage("No feature manager is " +
+                                "registered with the given type '" + type + "'").build()).build();
             }
             features = fm.getFeatures();
         } catch (DeviceManagementException e) {
             String msg = "Error occurred while retrieving the list of features of '" + type + "' device, which " +
                     "carries the id '" + id + "'";
             log.error(msg, e);
-            throw new UnexpectedServerErrorException(
-                    new ErrorResponse.ErrorResponseBuilder().setCode(500l).setMessage(msg).build());
+            return Response.serverError().entity(
+                    new ErrorResponse.ErrorResponseBuilder().setMessage(msg).build()).build();
         }
         return Response.status(Response.Status.OK).entity(features).build();
     }
@@ -216,13 +212,9 @@ public class DeviceManagementServiceImpl implements DeviceManagementService {
         } catch (SearchMgtException e) {
             String msg = "Error occurred while searching for devices that matches the provided selection criteria";
             log.error(msg, e);
-            throw new UnexpectedServerErrorException(
-                    new ErrorResponse.ErrorResponseBuilder().setCode(500l).setMessage(msg).build());
+            return Response.serverError().entity(
+                    new ErrorResponse.ErrorResponseBuilder().setMessage(msg).build()).build();
         }
-        if (devices == null || devices.size() == 0) {
-            Response.status(Response.Status.OK).entity(deviceList);
-        }
-
         deviceList.setList(devices);
         return Response.status(Response.Status.OK).entity(deviceList).build();
     }
@@ -237,23 +229,21 @@ public class DeviceManagementServiceImpl implements DeviceManagementService {
             @QueryParam("offset") int offset,
             @QueryParam("limit") int limit) {
         List<Application> applications;
+        //ApplicationList appList;
         ApplicationManagementProviderService amc;
         try {
             RequestValidationUtil.validateDeviceIdentifier(type, id);
 
             amc = DeviceMgtAPIUtils.getAppManagementService();
             applications = amc.getApplicationListForDevice(new DeviceIdentifier(id, type));
-            if (applications == null) {
-                throw new NotFoundException(
-                        new ErrorResponse.ErrorResponseBuilder().setCode(404l).setMessage("It is likely that " +
-                                "no applications is found upon the provided type and id").build());
-            }
+
+            //TODO: return app list
         } catch (ApplicationManagementException e) {
             String msg = "Error occurred while fetching the apps of the '" + type + "' device, which carries " +
                     "the id '" + id + "'";
             log.error(msg, e);
-            throw new UnexpectedServerErrorException(
-                    new ErrorResponse.ErrorResponseBuilder().setCode(500l).setMessage(msg).build());
+            return Response.serverError().entity(
+                    new ErrorResponse.ErrorResponseBuilder().setMessage(msg).build()).build();
         }
         return Response.status(Response.Status.OK).entity(applications).build();
     }
@@ -275,24 +265,18 @@ public class DeviceManagementServiceImpl implements DeviceManagementService {
             RequestValidationUtil.validateDeviceIdentifier(type, id);
 
             dms = DeviceMgtAPIUtils.getDeviceManagementService();
-            result = dms.getOperations(new DeviceIdentifier(id, type),request);
-            int resultCount = result.getRecordsTotal();
+            result = dms.getOperations(new DeviceIdentifier(id, type), request);
 
-            if (resultCount == 0) {
-                throw new NotFoundException(
-                        new ErrorResponse.ErrorResponseBuilder().setCode(404l).setMessage("It is likely that" +
-                                " no operation is found upon the provided type and id").build());
-            }
+            operationsList.setList((List<? extends Operation>) result.getData());
+            operationsList.setCount(result.getRecordsTotal());
+            return Response.status(Response.Status.OK).entity(operationsList).build();
         } catch (OperationManagementException e) {
             String msg = "Error occurred while fetching the operations for the '" + type + "' device, which " +
                     "carries the id '" + id + "'";
             log.error(msg, e);
-            throw new UnexpectedServerErrorException(
-                    new ErrorResponse.ErrorResponseBuilder().setCode(500l).setMessage(msg).build());
+            return Response.serverError().entity(
+                    new ErrorResponse.ErrorResponseBuilder().setMessage(msg).build()).build();
         }
-        operationsList.setList((List<? extends Operation>) result.getData());
-        operationsList.setCount(result.getRecordsTotal());
-        return Response.status(Response.Status.OK).entity(operationsList).build();
     }
 
     @GET
@@ -306,35 +290,15 @@ public class DeviceManagementServiceImpl implements DeviceManagementService {
 
             PolicyManagerService policyManagementService = DeviceMgtAPIUtils.getPolicyManagementService();
             Policy policy = policyManagementService.getAppliedPolicyToDevice(new DeviceIdentifier(id, type));
-            if (policy == null) {
-                throw new NotFoundException(
-                        new ErrorResponse.ErrorResponseBuilder().setCode(404l).setMessage("No policy has " +
-                                "been found for the '" + type + "' device, which carries the id '" + id + "'").build());
-            }
+
             return Response.status(Response.Status.OK).entity(policy).build();
         } catch (PolicyManagementException e) {
             String msg = "Error occurred while retrieving the current policy associated with the '" + type +
                     "' device, which carries the id '" + id + "'";
             log.error(msg, e);
-            throw new UnexpectedServerErrorException(
-                    new ErrorResponse.ErrorResponseBuilder().setCode(500l).setMessage(msg).build());
-        }
-    }
-
-    @GET
-    @Path("/types")
-    @Override
-    public Response getDeviceTypes() {
-        List<DeviceType> deviceTypes;
-        try {
-            deviceTypes = DeviceMgtAPIUtils.getDeviceManagementService().getAvailableDeviceTypes();
-        } catch (DeviceManagementException e) {
-            String msg = "Error occurred while fetching the list of device types.";
-            log.error(msg, e);
-            throw new UnexpectedServerErrorException(new ErrorResponse.ErrorResponseBuilder().
-                setCode(500l).setMessage(msg).build());
+            return Response.serverError().entity(
+                    new ErrorResponse.ErrorResponseBuilder().setMessage(msg).build()).build();
         }
-        return Response.status(Response.Status.OK).entity(deviceTypes).build();
     }
 
 }
diff --git a/components/device-mgt/org.wso2.carbon.device.mgt.api/src/main/java/org/wso2/carbon/device/mgt/jaxrs/service/impl/NotificationManagementServiceImpl.java b/components/device-mgt/org.wso2.carbon.device.mgt.api/src/main/java/org/wso2/carbon/device/mgt/jaxrs/service/impl/NotificationManagementServiceImpl.java
index 7b510223e2..b9afcfa605 100644
--- a/components/device-mgt/org.wso2.carbon.device.mgt.api/src/main/java/org/wso2/carbon/device/mgt/jaxrs/service/impl/NotificationManagementServiceImpl.java
+++ b/components/device-mgt/org.wso2.carbon.device.mgt.api/src/main/java/org/wso2/carbon/device/mgt/jaxrs/service/impl/NotificationManagementServiceImpl.java
@@ -20,19 +20,14 @@ package org.wso2.carbon.device.mgt.jaxrs.service.impl;
 
 import org.apache.commons.logging.Log;
 import org.apache.commons.logging.LogFactory;
-import org.wso2.carbon.device.mgt.common.DeviceIdentifier;
 import org.wso2.carbon.device.mgt.common.PaginationRequest;
 import org.wso2.carbon.device.mgt.common.PaginationResult;
 import org.wso2.carbon.device.mgt.common.notification.mgt.Notification;
 import org.wso2.carbon.device.mgt.common.notification.mgt.NotificationManagementException;
-import org.wso2.carbon.device.mgt.common.operation.mgt.Operation;
-import org.wso2.carbon.device.mgt.core.service.DeviceManagementProviderService;
-import org.wso2.carbon.device.mgt.jaxrs.NotificationContext;
 import org.wso2.carbon.device.mgt.jaxrs.beans.ErrorResponse;
 import org.wso2.carbon.device.mgt.jaxrs.beans.NotificationList;
 import org.wso2.carbon.device.mgt.jaxrs.service.api.NotificationManagementService;
-import org.wso2.carbon.device.mgt.jaxrs.service.impl.util.*;
-import org.wso2.carbon.device.mgt.jaxrs.service.impl.util.NotFoundException;
+import org.wso2.carbon.device.mgt.jaxrs.service.impl.util.RequestValidationUtil;
 import org.wso2.carbon.device.mgt.jaxrs.util.DeviceMgtAPIUtils;
 
 import javax.ws.rs.*;
@@ -55,36 +50,27 @@ public class NotificationManagementServiceImpl implements NotificationManagement
             @QueryParam("offset") int offset, @QueryParam("limit") int limit) {
 
         PaginationRequest request = new PaginationRequest(offset, limit);
-        PaginationResult result = null;
+        PaginationResult result;
 
         NotificationList notificationList = new NotificationList();
-        int resultCount = 0;
 
         String msg;
         try {
             if (status != null) {
                 RequestValidationUtil.validateNotificationStatus(status);
                 result = DeviceMgtAPIUtils.getNotificationManagementService().getNotificationsByStatus(
-                        Notification.Status.valueOf(status),request);
-                resultCount = result.getRecordsTotal();
+                        Notification.Status.valueOf(status), request);
             } else {
                 result = DeviceMgtAPIUtils.getNotificationManagementService().getAllNotifications(request);
             }
-
-            if (resultCount == 0) {
-                throw new NotFoundException(
-                        new ErrorResponse.ErrorResponseBuilder().setCode(404l).setMessage("No notification is " +
-                                "available to be retrieved.").build());
-            }
-
-            notificationList.setNotifications((List<Notification>) result.getData());
             notificationList.setCount(result.getRecordsTotal());
+            notificationList.setNotifications((List<Notification>) result.getData());
             return Response.status(Response.Status.OK).entity(notificationList).build();
         } catch (NotificationManagementException e) {
-            msg = "Error occurred while retrieving notification info";
+            msg = "Error occurred while retrieving notification list";
             log.error(msg, e);
-            throw new UnexpectedServerErrorException(
-                    new ErrorResponse.ErrorResponseBuilder().setCode(500l).setMessage(msg).build());
+            return Response.serverError().entity(
+                    new ErrorResponse.ErrorResponseBuilder().setMessage(msg).build()).build();
         }
     }
 
diff --git a/components/device-mgt/org.wso2.carbon.device.mgt.api/src/main/java/org/wso2/carbon/device/mgt/jaxrs/service/impl/PolicyManagementServiceImpl.java b/components/device-mgt/org.wso2.carbon.device.mgt.api/src/main/java/org/wso2/carbon/device/mgt/jaxrs/service/impl/PolicyManagementServiceImpl.java
index ca2a7a5096..455dc0f9ea 100644
--- a/components/device-mgt/org.wso2.carbon.device.mgt.api/src/main/java/org/wso2/carbon/device/mgt/jaxrs/service/impl/PolicyManagementServiceImpl.java
+++ b/components/device-mgt/org.wso2.carbon.device.mgt.api/src/main/java/org/wso2/carbon/device/mgt/jaxrs/service/impl/PolicyManagementServiceImpl.java
@@ -31,7 +31,6 @@ import org.wso2.carbon.device.mgt.jaxrs.beans.ErrorResponse;
 import org.wso2.carbon.device.mgt.jaxrs.beans.PolicyWrapper;
 import org.wso2.carbon.device.mgt.jaxrs.service.api.PolicyManagementService;
 import org.wso2.carbon.device.mgt.jaxrs.service.impl.util.*;
-import org.wso2.carbon.device.mgt.jaxrs.service.impl.util.NotFoundException;
 import org.wso2.carbon.device.mgt.jaxrs.beans.PolicyList;
 import org.wso2.carbon.device.mgt.jaxrs.service.impl.util.FilteringUtil;
 import org.wso2.carbon.device.mgt.jaxrs.util.DeviceMgtAPIUtils;
@@ -45,6 +44,8 @@ import org.wso2.carbon.device.mgt.jaxrs.beans.PriorityUpdatedPolicyWrapper;
 import javax.ws.rs.*;
 import javax.ws.rs.core.MediaType;
 import javax.ws.rs.core.Response;
+import java.net.URI;
+import java.net.URISyntaxException;
 import java.util.ArrayList;
 import java.util.List;
 
@@ -53,6 +54,7 @@ import java.util.List;
 @Consumes(MediaType.APPLICATION_JSON)
 public class PolicyManagementServiceImpl implements PolicyManagementService {
 
+    private static final String API_BASE_PATH = "/policies";
     private static final Log log = LogFactory.getLog(PolicyManagementServiceImpl.class);
 
     @POST
@@ -74,31 +76,38 @@ public class PolicyManagementServiceImpl implements PolicyManagementService {
                 String username = threadLocalCarbonContext.getUsername();
                 try {
                     if (!deviceAccessAuthorizationService.isUserAuthorized(deviceIdentifier, username)) {
-                        throw new UnauthorizedAccessException(
-                                new ErrorResponse.ErrorResponseBuilder().setCode(401l).setMessage
-                                        ("Current logged in user is not authorized to add policies").build());
+                        return Response.status(Response.Status.UNAUTHORIZED).entity(
+                                new ErrorResponse.ErrorResponseBuilder().setMessage
+                                        ("Current logged in user is not authorized to add policies").build()).build();
                     }
                 } catch (DeviceAccessAuthorizationException e) {
-                    String msg = "ErrorResponse occurred while checking if the current user is authorized to add a policy";
+                    String msg = "Error occurred while checking if the current user is authorized to add a policy";
                     log.error(msg, e);
-                    throw new UnexpectedServerErrorException(
-                            new ErrorResponse.ErrorResponseBuilder().setCode(500l).setMessage(msg).build());
+                    return Response.serverError().entity(
+                            new ErrorResponse.ErrorResponseBuilder().setMessage(msg).build()).build();
                 }
             }
 
             PolicyAdministratorPoint pap = policyManagementService.getPAP();
-            pap.addPolicy(policy);
-            return Response.status(Response.Status.CREATED).entity("Policy has been added successfully").build();
+            Policy createdPolicy = pap.addPolicy(policy);
+
+            return Response.created(new URI(API_BASE_PATH + "/" + createdPolicy.getId())).entity(createdPolicy).build();
         } catch (PolicyManagementException e) {
-            String msg = "ErrorResponse occurred while adding policy";
+            String msg = "Error occurred while adding policy";
             log.error(msg, e);
-            throw new UnexpectedServerErrorException(
-                    new ErrorResponse.ErrorResponseBuilder().setCode(500l).setMessage(msg).build());
+            return Response.serverError().entity(
+                    new ErrorResponse.ErrorResponseBuilder().setCode(500l).setMessage(msg).build()).build();
         } catch (DeviceManagementException e) {
-            String msg = "ErrorResponse occurred while retrieving device list.";
+            String msg = "Error occurred while retrieving device list.";
+            log.error(msg, e);
+            return Response.serverError().entity(
+                    new ErrorResponse.ErrorResponseBuilder().setCode(500l).setMessage(msg).build()).build();
+        } catch (URISyntaxException e) {
+            String msg = "Error occurred while composing the location URI, which represents information of the " +
+                    "newly created policy";
             log.error(msg, e);
-            throw new UnexpectedServerErrorException(
-                    new ErrorResponse.ErrorResponseBuilder().setCode(500l).setMessage(msg).build());
+            return Response.serverError().entity(
+                    new ErrorResponse.ErrorResponseBuilder().setMessage(msg).build()).build();
         }
     }
 
@@ -138,21 +147,14 @@ public class PolicyManagementServiceImpl implements PolicyManagementService {
         try {
             PolicyAdministratorPoint policyAdministratorPoint = policyManagementService.getPAP();
             policies = policyAdministratorPoint.getPolicies();
-            if (policies == null || policies.size() == 0) {
-                throw new NotFoundException(
-                        new ErrorResponse.ErrorResponseBuilder().setCode(404l).setMessage("No policies found.").build());
-            }
             targetPolicies.setCount(policies.size());
             filteredPolicies = FilteringUtil.getFilteredList(policies, offset, limit);
-            if (filteredPolicies.size() == 0) {
-                return Response.status(Response.Status.NOT_FOUND).entity("No policies found.").build();
-            }
             targetPolicies.setList(filteredPolicies);
         } catch (PolicyManagementException e) {
-            String msg = "ErrorResponse occurred while retrieving all available policies";
+            String msg = "Error occurred while retrieving all available policies";
             log.error(msg, e);
-            throw new UnexpectedServerErrorException(
-                    new ErrorResponse.ErrorResponseBuilder().setCode(500l).setMessage(msg).build());
+            return Response.serverError().entity(
+                    new ErrorResponse.ErrorResponseBuilder().setMessage(msg).build()).build();
         }
 
         return Response.status(Response.Status.OK).entity(targetPolicies).build();
@@ -168,14 +170,15 @@ public class PolicyManagementServiceImpl implements PolicyManagementService {
             PolicyAdministratorPoint policyAdministratorPoint = policyManagementService.getPAP();
             policy = policyAdministratorPoint.getPolicy(id);
             if (policy == null) {
-                throw new NotFoundException(
-                        new ErrorResponse.ErrorResponseBuilder().setCode(404l).setMessage("No policy found.").build());
+                return Response.status(Response.Status.NOT_FOUND).entity(
+                        new ErrorResponse.ErrorResponseBuilder().setMessage(
+                                "No policy found with the id '" + id + "'").build()).build();
             }
         } catch (PolicyManagementException e) {
-            String msg = "ErrorResponse occurred while retrieving policy corresponding to the id '" + id + "'";
+            String msg = "Error occurred while retrieving policy corresponding to the id '" + id + "'";
             log.error(msg, e);
-            throw new UnexpectedServerErrorException(
-                    new ErrorResponse.ErrorResponseBuilder().setCode(500l).setMessage(msg).build());
+            return Response.serverError().entity(
+                    new ErrorResponse.ErrorResponseBuilder().setMessage(msg).build()).build();
         }
         return Response.status(Response.Status.OK).entity(policy).build();
     }
@@ -190,22 +193,22 @@ public class PolicyManagementServiceImpl implements PolicyManagementService {
             Policy policy = this.getPolicyFromWrapper(policyWrapper);
             policy.setId(id);
             PolicyAdministratorPoint pap = policyManagementService.getPAP();
-            Policy exisitingPolicy = pap.getPolicy(id);
-            if (exisitingPolicy == null) {
+            Policy existingPolicy = pap.getPolicy(id);
+            if (existingPolicy == null) {
                 return Response.status(Response.Status.NOT_FOUND).entity("Policy not found.").build();
             }
             pap.updatePolicy(policy);
             return Response.status(Response.Status.OK).entity("Policy has successfully been updated.").build();
         } catch (PolicyManagementException e) {
-            String msg = "ErrorResponse occurred while updating the policy";
+            String msg = "Error occurred while updating the policy";
             log.error(msg, e);
-            throw new UnexpectedServerErrorException(
-                    new ErrorResponse.ErrorResponseBuilder().setCode(500l).setMessage(msg).build());
+            return Response.serverError().entity(
+                    new ErrorResponse.ErrorResponseBuilder().setMessage(msg).build()).build();
         } catch (DeviceManagementException e) {
-            String msg = "ErrorResponse occurred while retrieving the device list.";
+            String msg = "Error occurred while retrieving the device list.";
             log.error(msg, e);
-            throw new UnexpectedServerErrorException(
-                    new ErrorResponse.ErrorResponseBuilder().setCode(500l).setMessage(msg).build());
+            return Response.serverError().entity(
+                    new ErrorResponse.ErrorResponseBuilder().setMessage(msg).build()).build();
         }
     }
 
@@ -227,15 +230,15 @@ public class PolicyManagementServiceImpl implements PolicyManagementService {
         } catch (PolicyManagementException e) {
             String msg = "ErrorResponse occurred while removing policies";
             log.error(msg, e);
-            throw new UnexpectedServerErrorException(
-                    new ErrorResponse.ErrorResponseBuilder().setCode(500l).setMessage(msg).build());
+            return Response.serverError().entity(
+                    new ErrorResponse.ErrorResponseBuilder().setMessage(msg).build()).build();
         }
         if (policyDeleted) {
             return Response.status(Response.Status.OK).entity("Policies have been successfully deleted").build();
         } else {
             //TODO:Check of this logic is correct
-            throw new NotFoundException(
-                    new ErrorResponse.ErrorResponseBuilder().setCode(404l).setMessage("Policy doesn't exist").build());
+            return Response.status(Response.Status.NOT_FOUND).entity(
+                    new ErrorResponse.ErrorResponseBuilder().setMessage("Policy doesn't exist").build()).build();
         }
     }
 
@@ -256,18 +259,18 @@ public class PolicyManagementServiceImpl implements PolicyManagementService {
                 }
             }
         } catch (PolicyManagementException e) {
-            String msg = "ErrorResponse occurred while activating policies";
+            String msg = "Error occurred while activating policies";
             log.error(msg, e);
-            throw new UnexpectedServerErrorException(
-                    new ErrorResponse.ErrorResponseBuilder().setCode(500l).setMessage(msg).build());
+            return Response.serverError().entity(
+                    new ErrorResponse.ErrorResponseBuilder().setCode(500l).setMessage(msg).build()).build();
         }
         if (isPolicyActivated) {
             return Response.status(Response.Status.OK).entity("Selected policies have been successfully activated")
                     .build();
         } else {
-            throw new NotFoundException(
-                    new ErrorResponse.ErrorResponseBuilder().setCode(404l).setMessage("Selected policies have " +
-                            "not been activated").build());
+            return Response.status(Response.Status.NOT_FOUND).entity(
+                    new ErrorResponse.ErrorResponseBuilder().setMessage("Selected policies have " +
+                            "not been activated").build()).build();
         }
     }
 
@@ -290,16 +293,16 @@ public class PolicyManagementServiceImpl implements PolicyManagementService {
         } catch (PolicyManagementException e) {
             String msg = "Exception in inactivating policies.";
             log.error(msg, e);
-            throw new UnexpectedServerErrorException(
-                    new ErrorResponse.ErrorResponseBuilder().setCode(500l).setMessage(msg).build());
+            return Response.serverError().entity(
+                    new ErrorResponse.ErrorResponseBuilder().setMessage(msg).build()).build();
         }
         if (isPolicyDeActivated) {
             return Response.status(Response.Status.OK).entity("Selected policies have been successfully " +
-                                                                      "deactivated").build();
+                    "deactivated").build();
         } else {
-            throw new NotFoundException(
-                    new ErrorResponse.ErrorResponseBuilder().setCode(404l).setMessage("Selected policies have " +
-                            "not been deactivated").build());
+            return Response.status(Response.Status.NOT_FOUND).entity(
+                    new ErrorResponse.ErrorResponseBuilder().setMessage("Selected policies have " +
+                            "not been deactivated").build()).build();
         }
     }
 
@@ -315,8 +318,8 @@ public class PolicyManagementServiceImpl implements PolicyManagementService {
         } catch (PolicyManagementException e) {
             String msg = "Exception in applying changes.";
             log.error(msg, e);
-            throw new UnexpectedServerErrorException(
-                    new ErrorResponse.ErrorResponseBuilder().setCode(500l).setMessage(msg).build());
+            return Response.serverError().entity(
+                    new ErrorResponse.ErrorResponseBuilder().setCode(500l).setMessage(msg).build()).build();
         }
         return Response.status(Response.Status.OK).entity("Changes have been successfully updated.").build();
     }
@@ -340,17 +343,17 @@ public class PolicyManagementServiceImpl implements PolicyManagementService {
         } catch (PolicyManagementException e) {
             String error = "Exception in updating policy priorities.";
             log.error(error, e);
-            throw new UnexpectedServerErrorException(
-                    new ErrorResponse.ErrorResponseBuilder().setCode(500l).setMessage(error).build());
+            return Response.serverError().entity(
+                    new ErrorResponse.ErrorResponseBuilder().setMessage(error).build()).build();
         }
         if (policiesUpdated) {
             return Response.status(Response.Status.OK).entity("Policy Priorities successfully "
                     + "updated.").build();
 
         } else {
-            throw new NotFoundException(
+            return Response.status(Response.Status.NOT_FOUND).entity(
                     new ErrorResponse.ErrorResponseBuilder().setCode(400l).setMessage("Policy priorities did "
-                            + "not update. Bad Request.").build());
+                            + "not update. Bad Request.").build()).build();
         }
     }
 
diff --git a/components/device-mgt/org.wso2.carbon.device.mgt.api/src/main/java/org/wso2/carbon/device/mgt/jaxrs/service/impl/RoleManagementServiceImpl.java b/components/device-mgt/org.wso2.carbon.device.mgt.api/src/main/java/org/wso2/carbon/device/mgt/jaxrs/service/impl/RoleManagementServiceImpl.java
index 599d4345be..4e788411e3 100644
--- a/components/device-mgt/org.wso2.carbon.device.mgt.api/src/main/java/org/wso2/carbon/device/mgt/jaxrs/service/impl/RoleManagementServiceImpl.java
+++ b/components/device-mgt/org.wso2.carbon.device.mgt.api/src/main/java/org/wso2/carbon/device/mgt/jaxrs/service/impl/RoleManagementServiceImpl.java
@@ -23,14 +23,12 @@ import org.apache.commons.logging.LogFactory;
 import org.wso2.carbon.CarbonConstants;
 import org.wso2.carbon.base.MultitenantConstants;
 import org.wso2.carbon.device.mgt.jaxrs.beans.ErrorResponse;
-import org.wso2.carbon.device.mgt.jaxrs.service.api.RoleManagementService;
-import org.wso2.carbon.device.mgt.jaxrs.service.impl.util.*;
-import org.wso2.carbon.device.mgt.jaxrs.service.impl.util.NotFoundException;
+import org.wso2.carbon.device.mgt.jaxrs.beans.RoleInfo;
 import org.wso2.carbon.device.mgt.jaxrs.beans.RoleList;
+import org.wso2.carbon.device.mgt.jaxrs.service.api.RoleManagementService;
 import org.wso2.carbon.device.mgt.jaxrs.service.impl.util.FilteringUtil;
-import org.wso2.carbon.device.mgt.jaxrs.service.impl.util.UnexpectedServerErrorException;
+import org.wso2.carbon.device.mgt.jaxrs.service.impl.util.RequestValidationUtil;
 import org.wso2.carbon.device.mgt.jaxrs.util.DeviceMgtAPIUtils;
-import org.wso2.carbon.device.mgt.jaxrs.beans.RoleWrapper;
 import org.wso2.carbon.device.mgt.jaxrs.util.SetReferenceTransformer;
 import org.wso2.carbon.user.api.*;
 import org.wso2.carbon.user.mgt.UserRealmProxy;
@@ -40,6 +38,8 @@ import org.wso2.carbon.user.mgt.common.UserAdminException;
 import javax.ws.rs.*;
 import javax.ws.rs.core.MediaType;
 import javax.ws.rs.core.Response;
+import java.net.URI;
+import java.net.URISyntaxException;
 import java.util.ArrayList;
 import java.util.Arrays;
 import java.util.List;
@@ -49,6 +49,7 @@ import java.util.List;
 @Consumes(MediaType.APPLICATION_JSON)
 public class RoleManagementServiceImpl implements RoleManagementService {
 
+    private static final String API_BASE_PATH = "/roles";
     private static final Log log = LogFactory.getLog(RoleManagementServiceImpl.class);
 
     @GET
@@ -61,25 +62,20 @@ public class RoleManagementServiceImpl implements RoleManagementService {
         List<String> filteredRoles;
         RoleList targetRoles = new RoleList();
         try {
+            //Get the total role count that matches the given filter
             filteredRoles = getRolesFromUserStore(filter);
-            if (filteredRoles == null || filteredRoles.size() == 0) {
-                throw new NotFoundException(
-                        new ErrorResponse.ErrorResponseBuilder().setCode(404l).setMessage("No roles found.").build());
-            }
             targetRoles.setCount(filteredRoles.size());
+
             filteredRoles = FilteringUtil.getFilteredList(getRolesFromUserStore(filter), offset, limit);
-            if (filteredRoles.size() == 0) {
-                throw new NotFoundException(
-                        new ErrorResponse.ErrorResponseBuilder().setCode(404l).setMessage("No roles found").build());
-            }
             targetRoles.setList(filteredRoles);
+
+            return Response.ok().entity(targetRoles).build();
         } catch (UserStoreException e) {
             String msg = "Error occurred while retrieving roles from the underlying user stores";
             log.error(msg, e);
-            throw new UnexpectedServerErrorException(
-                    new ErrorResponse.ErrorResponseBuilder().setCode(500l).setMessage(msg).build());
+            return Response.serverError().entity(
+                    new ErrorResponse.ErrorResponseBuilder().setMessage(msg).build()).build();
         }
-        return Response.status(Response.Status.OK).entity(targetRoles).build();
     }
 
     @GET
@@ -91,35 +87,39 @@ public class RoleManagementServiceImpl implements RoleManagementService {
         RequestValidationUtil.validateRoleName(roleName);
         try {
             final UserRealm userRealm = DeviceMgtAPIUtils.getUserRealm();
-            org.wso2.carbon.user.core.UserRealm userRealmCore = null;
-            final UIPermissionNode rolePermissions;
-            if (userRealm instanceof org.wso2.carbon.user.core.UserRealm) {
-                userRealmCore = (org.wso2.carbon.user.core.UserRealm) userRealm;
+            if (!userRealm.getUserStoreManager().isExistingRole(roleName)) {
+                return Response.status(Response.Status.NOT_FOUND).entity(new ErrorResponse.ErrorResponseBuilder().setMessage(
+                        "No role exists with the name '" + roleName + "'").build()).build();
             }
-            final UserRealmProxy userRealmProxy = new UserRealmProxy(userRealmCore);
-            rolePermissions = this.getUIPermissionNode(roleName, userRealmProxy);
+
+            final UIPermissionNode rolePermissions = this.getUIPermissionNode(roleName, userRealm);
             if (rolePermissions == null) {
-                throw new NotFoundException(
-                        new ErrorResponse.ErrorResponseBuilder().setCode(404l).setMessage("No permissions found" +
-                                " for the role '" + roleName + "'").build());
+                if (log.isDebugEnabled()) {
+                    log.debug("No permissions found for the role '" + roleName + "'");
+                }
             }
             return Response.status(Response.Status.OK).entity(rolePermissions).build();
         } catch (UserAdminException e) {
             String msg = "Error occurred while retrieving the permissions of role '" + roleName + "'";
             log.error(msg, e);
-            throw new UnexpectedServerErrorException(
-                    new ErrorResponse.ErrorResponseBuilder().setCode(500l).setMessage(msg).build());
+            return Response.serverError().entity(
+                    new ErrorResponse.ErrorResponseBuilder().setMessage(msg).build()).build();
         } catch (UserStoreException e) {
             String msg = "Error occurred while retrieving the underlying user realm attached to the " +
                     "current logged in user";
             log.error(msg, e);
-            throw new UnexpectedServerErrorException(
-                    new ErrorResponse.ErrorResponseBuilder().setCode(500l).setMessage(msg).build());
+            return Response.serverError().entity(
+                    new ErrorResponse.ErrorResponseBuilder().setMessage(msg).build()).build();
         }
     }
 
-    private UIPermissionNode getUIPermissionNode(String roleName, UserRealmProxy userRealmProxy)
+    private UIPermissionNode getUIPermissionNode(String roleName, UserRealm userRealm)
             throws UserAdminException {
+        org.wso2.carbon.user.core.UserRealm userRealmCore = null;
+        if (userRealm instanceof org.wso2.carbon.user.core.UserRealm) {
+            userRealmCore = (org.wso2.carbon.user.core.UserRealm) userRealm;
+        }
+        final UserRealmProxy userRealmProxy = new UserRealmProxy(userRealmCore);
         final UIPermissionNode rolePermissions =
                 userRealmProxy.getRolePermissions(roleName, MultitenantConstants.SUPER_TENANT_ID);
         UIPermissionNode[] deviceMgtPermissions = new UIPermissionNode[2];
@@ -144,42 +144,36 @@ public class RoleManagementServiceImpl implements RoleManagementService {
     @Override
     public Response getRole(@PathParam("roleName") String roleName,
                             @HeaderParam("If-Modified-Since") String ifModifiedSince) {
+        if (log.isDebugEnabled()) {
+            log.debug("Getting the list of user roles");
+        }
         RequestValidationUtil.validateRoleName(roleName);
-        RoleWrapper roleWrapper = new RoleWrapper();
+        RoleInfo roleInfo = new RoleInfo();
         try {
             final UserStoreManager userStoreManager = DeviceMgtAPIUtils.getUserStoreManager();
             final UserRealm userRealm = DeviceMgtAPIUtils.getUserRealm();
-            org.wso2.carbon.user.core.UserRealm userRealmCore = null;
-            if (userRealm instanceof org.wso2.carbon.user.core.UserRealm) {
-                userRealmCore = (org.wso2.carbon.user.core.UserRealm) userRealm;
+            if (!userStoreManager.isExistingRole(roleName)) {
+                return Response.status(Response.Status.NOT_FOUND).entity(
+                        new ErrorResponse.ErrorResponseBuilder().setMessage("No role exists with the name '" +
+                                roleName + "'").build()).build();
             }
+            roleInfo.setRoleName(roleName);
+            roleInfo.setUsers(userStoreManager.getUserListOfRole(roleName));
+            // Get the permission nodes and hand picking only device management and login perms
+            final UIPermissionNode rolePermissions = this.getUIPermissionNode(roleName, userRealm);
+            List<String> permList = new ArrayList<>();
+            this.iteratePermissions(rolePermissions, permList);
+            roleInfo.setPermissionList(rolePermissions);
+            String[] permListAr = new String[permList.size()];
+            roleInfo.setPermissions(permList.toArray(permListAr));
 
-            final UserRealmProxy userRealmProxy = new UserRealmProxy(userRealmCore);
-            if (log.isDebugEnabled()) {
-                log.debug("Getting the list of user roles");
-            }
-            if (userStoreManager.isExistingRole(roleName)) {
-                roleWrapper.setRoleName(roleName);
-                roleWrapper.setUsers(userStoreManager.getUserListOfRole(roleName));
-                // Get the permission nodes and hand picking only device management and login perms
-                final UIPermissionNode rolePermissions = getUIPermissionNode(roleName, userRealmProxy);
-                List<String> permList = new ArrayList<>();
-                this.iteratePermissions(rolePermissions, permList);
-                roleWrapper.setPermissionList(rolePermissions);
-                String[] permListAr = new String[permList.size()];
-                roleWrapper.setPermissions(permList.toArray(permListAr));
-            } else {
-                throw new NotFoundException(
-                        new ErrorResponse.ErrorResponseBuilder().setCode(404l).setMessage("Role name doesn't exist.")
-                                .build());
-            }
+            return Response.status(Response.Status.OK).entity(roleInfo).build();
         } catch (UserStoreException | UserAdminException e) {
             String msg = "Error occurred while retrieving the user role '" + roleName + "'";
             log.error(msg, e);
-            throw new UnexpectedServerErrorException(
-                    new ErrorResponse.ErrorResponseBuilder().setCode(500l).setMessage(msg).build());
+            return Response.serverError().entity(
+                    new ErrorResponse.ErrorResponseBuilder().setMessage(msg).build()).build();
         }
-        return Response.status(Response.Status.OK).entity(roleWrapper).build();
     }
 
     private List<String> iteratePermissions(UIPermissionNode uiPermissionNode, List<String> list) {
@@ -194,78 +188,97 @@ public class RoleManagementServiceImpl implements RoleManagementService {
 
     @POST
     @Override
-    public Response addRole(RoleWrapper roleWrapper) {
-        RequestValidationUtil.validateRoleDetails(roleWrapper);
-        RequestValidationUtil.validateRoleName(roleWrapper.getRoleName());
+    public Response addRole(RoleInfo roleInfo) {
+        RequestValidationUtil.validateRoleDetails(roleInfo);
+        RequestValidationUtil.validateRoleName(roleInfo.getRoleName());
         try {
             UserStoreManager userStoreManager = DeviceMgtAPIUtils.getUserStoreManager();
             if (log.isDebugEnabled()) {
-                log.debug("Persisting the role to user store");
+                log.debug("Persisting the role in the underlying user store");
             }
             Permission[] permissions = null;
-            if (roleWrapper.getPermissions() != null && roleWrapper.getPermissions().length > 0) {
-                permissions = new Permission[roleWrapper.getPermissions().length];
-
+            if (roleInfo.getPermissions() != null && roleInfo.getPermissions().length > 0) {
+                permissions = new Permission[roleInfo.getPermissions().length];
                 for (int i = 0; i < permissions.length; i++) {
-                    String permission = roleWrapper.getPermissions()[i];
+                    String permission = roleInfo.getPermissions()[i];
                     permissions[i] = new Permission(permission, CarbonConstants.UI_PERMISSION_ACTION);
                 }
             }
-            userStoreManager.addRole(roleWrapper.getRoleName(), roleWrapper.getUsers(), permissions);
+            userStoreManager.addRole(roleInfo.getRoleName(), roleInfo.getUsers(), permissions);
+
+            //TODO fix what's returned in the entity
+            return Response.created(new URI(API_BASE_PATH + "/" + roleInfo.getRoleName())).entity(
+                    "Role '" + roleInfo.getRoleName() + "' has " +
+                            "successfully been added").build();
         } catch (UserStoreException e) {
-            String msg = "Error occurred while adding role '" + roleWrapper.getRoleName() + "'";
+            String msg = "Error occurred while adding role '" + roleInfo.getRoleName() + "'";
+            log.error(msg, e);
+            return Response.serverError().entity(
+                    new ErrorResponse.ErrorResponseBuilder().setMessage(msg).build()).build();
+        } catch (URISyntaxException e) {
+            String msg = "Error occurred while composing the URI at which the information of the newly created role " +
+                    "can be retrieved";
             log.error(msg, e);
-            throw new UnexpectedServerErrorException(
-                    new ErrorResponse.ErrorResponseBuilder().setCode(500l).setMessage(msg).build());
+            return Response.serverError().entity(
+                    new ErrorResponse.ErrorResponseBuilder().setMessage(msg).build()).build();
         }
-        return Response.status(Response.Status.OK).entity("Role '" + roleWrapper.getRoleName() + "' has " +
-                "successfully been added").build();
     }
 
     @PUT
     @Path("/{roleName}")
     @Override
-    public Response updateRole(@PathParam("roleName") String roleName, RoleWrapper roleWrapper) {
+    public Response updateRole(@PathParam("roleName") String roleName, RoleInfo roleInfo) {
         RequestValidationUtil.validateRoleName(roleName);
-        RequestValidationUtil.validateRoleDetails(roleWrapper);
-        String newRoleName = roleWrapper.getRoleName();
+        RequestValidationUtil.validateRoleDetails(roleInfo);
         try {
-            final UserStoreManager userStoreManager = DeviceMgtAPIUtils.getUserStoreManager();
-            final AuthorizationManager authorizationManager = DeviceMgtAPIUtils.getAuthorizationManager();
+            final UserRealm userRealm = DeviceMgtAPIUtils.getUserRealm();
+            final UserStoreManager userStoreManager = userRealm.getUserStoreManager();
+            if (!userStoreManager.isExistingRole(roleName)) {
+                return Response.status(Response.Status.NOT_FOUND).entity(
+                        new ErrorResponse.ErrorResponseBuilder().setMessage("No role exists with the name '" +
+                                roleName + "'").build()).build();
+            }
+
+            final AuthorizationManager authorizationManager = userRealm.getAuthorizationManager();
             if (log.isDebugEnabled()) {
                 log.debug("Updating the role to user store");
             }
+
+            String newRoleName = roleInfo.getRoleName();
             if (newRoleName != null && !roleName.equals(newRoleName)) {
                 userStoreManager.updateRoleName(roleName, newRoleName);
             }
-            if (roleWrapper.getUsers() != null) {
+
+            if (roleInfo.getUsers() != null) {
                 SetReferenceTransformer<String> transformer = new SetReferenceTransformer<>();
                 transformer.transform(Arrays.asList(userStoreManager.getUserListOfRole(newRoleName)),
-                        Arrays.asList(roleWrapper.getUsers()));
+                        Arrays.asList(roleInfo.getUsers()));
                 final String[] usersToAdd = transformer.getObjectsToAdd().toArray(new String[transformer
                         .getObjectsToAdd().size()]);
                 final String[] usersToDelete = transformer.getObjectsToRemove().toArray(new String[transformer
                         .getObjectsToRemove().size()]);
                 userStoreManager.updateUserListOfRole(newRoleName, usersToDelete, usersToAdd);
             }
-            if (roleWrapper.getPermissions() != null) {
+
+            if (roleInfo.getPermissions() != null) {
                 // Delete all authorizations for the current role before authorizing the permission tree
                 authorizationManager.clearRoleAuthorization(roleName);
-                if (roleWrapper.getPermissions().length > 0) {
-                    for (int i = 0; i < roleWrapper.getPermissions().length; i++) {
-                        String permission = roleWrapper.getPermissions()[i];
+                if (roleInfo.getPermissions().length > 0) {
+                    for (int i = 0; i < roleInfo.getPermissions().length; i++) {
+                        String permission = roleInfo.getPermissions()[i];
                         authorizationManager.authorizeRole(roleName, permission, CarbonConstants.UI_PERMISSION_ACTION);
                     }
                 }
             }
+            //TODO: Need to send the updated role information in the entity back to the client
+            return Response.status(Response.Status.OK).entity("Role '" + roleInfo.getRoleName() + "' has " +
+                    "successfully been updated").build();
         } catch (UserStoreException e) {
             String msg = "Error occurred while updating role '" + roleName + "'";
             log.error(msg, e);
-            throw new UnexpectedServerErrorException(
-                    new ErrorResponse.ErrorResponseBuilder().setCode(500l).setMessage(msg).build());
+            return Response.serverError().entity(
+                    new ErrorResponse.ErrorResponseBuilder().setMessage(msg).build()).build();
         }
-        return Response.status(Response.Status.OK).entity("Role '" + roleWrapper.getRoleName() + "' has " +
-                "successfully been updated").build();
     }
 
     @DELETE
@@ -274,22 +287,29 @@ public class RoleManagementServiceImpl implements RoleManagementService {
     public Response deleteRole(@PathParam("roleName") String roleName) {
         RequestValidationUtil.validateRoleName(roleName);
         try {
-            final UserStoreManager userStoreManager = DeviceMgtAPIUtils.getUserStoreManager();
-            final AuthorizationManager authorizationManager = DeviceMgtAPIUtils.getAuthorizationManager();
+            final UserRealm userRealm = DeviceMgtAPIUtils.getUserRealm();
+            final UserStoreManager userStoreManager = userRealm.getUserStoreManager();
+            if (!userStoreManager.isExistingRole(roleName)) {
+                return Response.status(Response.Status.NOT_FOUND).entity(
+                        new ErrorResponse.ErrorResponseBuilder().setMessage("No role exists with the name '" +
+                                roleName + "'").build()).build();
+            }
+
+            final AuthorizationManager authorizationManager = userRealm.getAuthorizationManager();
             if (log.isDebugEnabled()) {
                 log.debug("Deleting the role in user store");
             }
             userStoreManager.deleteRole(roleName);
             // Delete all authorizations for the current role before deleting
             authorizationManager.clearRoleAuthorization(roleName);
+
+            return Response.status(Response.Status.OK).build();
         } catch (UserStoreException e) {
             String msg = "Error occurred while deleting the role '" + roleName + "'";
             log.error(msg, e);
-            throw new UnexpectedServerErrorException(
-                    new ErrorResponse.ErrorResponseBuilder().setCode(500l).setMessage(msg).build());
+            return Response.serverError().entity(
+                    new ErrorResponse.ErrorResponseBuilder().setMessage(msg).build()).build();
         }
-        return Response.status(Response.Status.OK).entity("Role '" + roleName + "' has " +
-                "successfully been deleted").build();
     }
 
     @PUT
@@ -312,20 +332,21 @@ public class RoleManagementServiceImpl implements RoleManagementService {
                     .getObjectsToRemove().size()]);
 
             userStoreManager.updateUserListOfRole(roleName, usersToDelete, usersToAdd);
+
+            return Response.status(Response.Status.OK).entity("Role '" + roleName + "' has " +
+                    "successfully been updated with the user list").build();
         } catch (UserStoreException e) {
             String msg = "Error occurred while updating the users of the role '" + roleName + "'";
             log.error(msg, e);
-            throw new UnexpectedServerErrorException(
-                    new ErrorResponse.ErrorResponseBuilder().setCode(500l).setMessage(msg).build());
+            return Response.serverError().entity(
+                    new ErrorResponse.ErrorResponseBuilder().setMessage(msg).build()).build();
         }
-        return Response.status(Response.Status.OK).entity("Role '" + roleName + "' has " +
-                "successfully been updated with the user list").build();
     }
 
     private List<String> getRolesFromUserStore(String filter) throws UserStoreException {
         UserStoreManager userStoreManager = DeviceMgtAPIUtils.getUserStoreManager();
         String[] roles;
-        boolean filterRolesByName = ((filter == null) || filter.isEmpty() ? false : true);
+        boolean filterRolesByName = (!((filter == null) || filter.isEmpty()));
         if (log.isDebugEnabled()) {
             log.debug("Getting the list of user roles");
         }
@@ -334,10 +355,10 @@ public class RoleManagementServiceImpl implements RoleManagementService {
         List<String> filteredRoles = new ArrayList<>();
         for (String role : roles) {
             if (!(role.startsWith("Internal/") || role.startsWith("Authentication/") || role.startsWith("Application/"))) {
-                if(!filterRolesByName) {
+                if (!filterRolesByName) {
                     filteredRoles.add(role);
-                } else{
-                    if(role.contains(filter)){
+                } else {
+                    if (role.contains(filter)) {
                         filteredRoles.add(role);
                     }
                 }
diff --git a/components/device-mgt/org.wso2.carbon.device.mgt.api/src/main/java/org/wso2/carbon/device/mgt/jaxrs/service/impl/UserManagementServiceImpl.java b/components/device-mgt/org.wso2.carbon.device.mgt.api/src/main/java/org/wso2/carbon/device/mgt/jaxrs/service/impl/UserManagementServiceImpl.java
index 60b4388b1f..41524f8862 100644
--- a/components/device-mgt/org.wso2.carbon.device.mgt.api/src/main/java/org/wso2/carbon/device/mgt/jaxrs/service/impl/UserManagementServiceImpl.java
+++ b/components/device-mgt/org.wso2.carbon.device.mgt.api/src/main/java/org/wso2/carbon/device/mgt/jaxrs/service/impl/UserManagementServiceImpl.java
@@ -21,24 +21,19 @@ package org.wso2.carbon.device.mgt.jaxrs.service.impl;
 import org.apache.commons.lang.StringUtils;
 import org.apache.commons.logging.Log;
 import org.apache.commons.logging.LogFactory;
-import org.wso2.carbon.context.CarbonContext;
-import org.wso2.carbon.device.mgt.common.DeviceManagementException;
-import org.wso2.carbon.device.mgt.core.service.DeviceManagementProviderService;
-import org.wso2.carbon.device.mgt.core.service.EmailMetaInfo;
 import org.wso2.carbon.device.mgt.jaxrs.beans.*;
 import org.wso2.carbon.device.mgt.jaxrs.service.api.UserManagementService;
-import org.wso2.carbon.device.mgt.jaxrs.service.impl.util.*;
-import org.wso2.carbon.device.mgt.jaxrs.service.impl.util.NotFoundException;
 import org.wso2.carbon.device.mgt.jaxrs.util.Constants;
 import org.wso2.carbon.device.mgt.jaxrs.util.CredentialManagementResponseBuilder;
 import org.wso2.carbon.device.mgt.jaxrs.util.DeviceMgtAPIUtils;
 import org.wso2.carbon.user.api.UserStoreException;
 import org.wso2.carbon.user.api.UserStoreManager;
-import org.wso2.carbon.utils.multitenancy.MultitenantConstants;
 
 import javax.ws.rs.*;
 import javax.ws.rs.core.MediaType;
 import javax.ws.rs.core.Response;
+import java.net.URI;
+import java.net.URISyntaxException;
 import java.util.*;
 
 @Path("/users")
@@ -47,117 +42,59 @@ import java.util.*;
 public class UserManagementServiceImpl implements UserManagementService {
 
     private static final String ROLE_EVERYONE = "Internal/everyone";
+    private static final String API_BASE_PATH = "/users";
     private static final Log log = LogFactory.getLog(UserManagementServiceImpl.class);
 
     @POST
     @Override
-    public Response addUser(UserInfo userWrapper) {
+    public Response addUser(UserInfo userInfo) {
         try {
             UserStoreManager userStoreManager = DeviceMgtAPIUtils.getUserStoreManager();
-            if (userStoreManager.isExistingUser(userWrapper.getUsername())) {
+            if (userStoreManager.isExistingUser(userInfo.getUsername())) {
                 // if user already exists
                 if (log.isDebugEnabled()) {
-                    log.debug("User by username: " + userWrapper.getUsername() +
+                    log.debug("User by username: " + userInfo.getUsername() +
                             " already exists. Therefore, request made to add user was refused.");
                 }
                 // returning response with bad request state
-                throw new ConflictException(
-                        new ErrorResponse.ErrorResponseBuilder().setCode(409l).setMessage("User by username: " +
-                                userWrapper.getUsername() +  " already exists. Therefore, request made to add user " +
-                                "was refused.").build());
-            } else {
-                String initialUserPassword = this.generateInitialUserPassword();
-                Map<String, String> defaultUserClaims =
-                        this.buildDefaultUserClaims(userWrapper.getFirstname(), userWrapper.getLastname(),
-                                userWrapper.getEmailAddress());
-                // calling addUser method of carbon user api
-                userStoreManager.addUser(userWrapper.getUsername(), initialUserPassword,
-                        userWrapper.getRoles(), defaultUserClaims, null);
-                // invite newly added user to enroll device
-                this.inviteNewlyAddedUserToEnrollDevice(userWrapper.getUsername(), initialUserPassword);
-                // Outputting debug message upon successful addition of user
-                if (log.isDebugEnabled()) {
-                    log.debug("User '" + userWrapper.getUsername() + "' has successfully been added.");
-                }
-                // returning response with success state
-                return Response.status(Response.Status.CREATED).entity("User by username: " + userWrapper.getUsername() +
-                        " was successfully added.").build();
+                return Response.status(Response.Status.CONFLICT).entity(
+                        new ErrorResponse.ErrorResponseBuilder().setMessage("User by username: " +
+                                userInfo.getUsername() + " already exists. Therefore, request made to add user " +
+                                "was refused.").build()).build();
+            }
+
+            String initialUserPassword = this.generateInitialUserPassword();
+            Map<String, String> defaultUserClaims =
+                    this.buildDefaultUserClaims(userInfo.getFirstname(), userInfo.getLastname(),
+                            userInfo.getEmailAddress());
+            // calling addUser method of carbon user api
+            userStoreManager.addUser(userInfo.getUsername(), initialUserPassword,
+                    userInfo.getRoles(), defaultUserClaims, null);
+            // Outputting debug message upon successful addition of user
+            if (log.isDebugEnabled()) {
+                log.debug("User '" + userInfo.getUsername() + "' has successfully been added.");
+            }
+
+            BasicUserInfo createdUserInfo = this.getBasicUserInfo(userInfo.getUsername());
+            // Outputting debug message upon successful retrieval of user
+            if (log.isDebugEnabled()) {
+                log.debug("User by username: " + userInfo.getUsername() + " was found.");
             }
+            return Response.created(new URI(API_BASE_PATH + "/" + userInfo.getUsername())).entity(
+                    createdUserInfo).build();
         } catch (UserStoreException e) {
-            String msg = "Exception in trying to add user '" + userWrapper.getUsername() + "' to the user store";
+            String msg = "Error occurred while trying to add user '" + userInfo.getUsername() + "' to the " +
+                    "underlying user management system";
             log.error(msg, e);
-            throw new UnexpectedServerErrorException(
-                    new ErrorResponse.ErrorResponseBuilder().setCode(500l).setMessage(msg).build());
-        } catch (DeviceManagementException e) {
-            String msg = "ErrorResponse occurred while inviting user to enroll the device";
+            return Response.serverError().entity(
+                    new ErrorResponse.ErrorResponseBuilder().setMessage(msg).build()).build();
+        } catch (URISyntaxException e) {
+            String msg = "Error occurred while composing the location URI, which represents information of the " +
+                    "newly created user '" + userInfo.getUsername() + "'";
             log.error(msg, e);
-            throw new UnexpectedServerErrorException(
-                    new ErrorResponse.ErrorResponseBuilder().setCode(500l).setMessage(msg).build());
-        }
-    }
-
-    private Map<String, String> buildDefaultUserClaims(String firstname, String lastname, String emailAddress) {
-        Map<String, String> defaultUserClaims = new HashMap<>();
-        defaultUserClaims.put(Constants.USER_CLAIM_FIRST_NAME, firstname);
-        defaultUserClaims.put(Constants.USER_CLAIM_LAST_NAME, lastname);
-        defaultUserClaims.put(Constants.USER_CLAIM_EMAIL_ADDRESS, emailAddress);
-        if (log.isDebugEnabled()) {
-            log.debug("Default claim map is created for new user: " + defaultUserClaims.toString());
-        }
-        return defaultUserClaims;
-    }
-
-    private String generateInitialUserPassword() {
-        int passwordLength = 6;
-        //defining the pool of characters to be used for initial password generation
-        String lowerCaseCharset = "abcdefghijklmnopqrstuvwxyz";
-        String upperCaseCharset = "ABCDEFGHIJKLMNOPQRSTUVWXYZ";
-        String numericCharset = "0123456789";
-        Random randomGenerator = new Random();
-        String totalCharset = lowerCaseCharset + upperCaseCharset + numericCharset;
-        int totalCharsetLength = totalCharset.length();
-        StringBuilder initialUserPassword = new StringBuilder();
-        for (int i = 0; i < passwordLength; i++) {
-            initialUserPassword
-                    .append(totalCharset.charAt(randomGenerator.nextInt(totalCharsetLength)));
-        }
-        if (log.isDebugEnabled()) {
-            log.debug("Initial user password is created for new user: " + initialUserPassword);
-        }
-        return initialUserPassword.toString();
-    }
-
-    private void inviteNewlyAddedUserToEnrollDevice(String username,
-                                                    String password) throws DeviceManagementException, UserStoreException {
-        if (log.isDebugEnabled()) {
-            log.debug("Sending invitation mail to user by username: " + username);
-        }
-        String tenantDomain = CarbonContext.getThreadLocalCarbonContext().getTenantDomain();
-        if (MultitenantConstants.SUPER_TENANT_DOMAIN_NAME.equalsIgnoreCase(tenantDomain)) {
-            tenantDomain = "";
-        }
-        if (!username.contains("/")) {
-            username = "/" + username;
+            return Response.serverError().entity(
+                    new ErrorResponse.ErrorResponseBuilder().setMessage(msg).build()).build();
         }
-        String[] usernameBits = username.split("/");
-        DeviceManagementProviderService deviceManagementProviderService = DeviceMgtAPIUtils.getDeviceManagementService();
-
-        Properties props = new Properties();
-        props.setProperty("username", usernameBits[1]);
-        props.setProperty("domain-name", tenantDomain);
-        props.setProperty("first-name", getClaimValue(usernameBits[1], Constants.USER_CLAIM_FIRST_NAME));
-        props.setProperty("password", password);
-
-        String recipient = getClaimValue(usernameBits[1], Constants.USER_CLAIM_EMAIL_ADDRESS);
-
-        EmailMetaInfo metaInfo = new EmailMetaInfo(recipient, props);
-
-        deviceManagementProviderService.sendRegistrationEmail(metaInfo);
-    }
-
-    private String getClaimValue(String username, String claimUri) throws UserStoreException {
-        UserStoreManager userStoreManager = DeviceMgtAPIUtils.getUserStoreManager();
-        return userStoreManager.getUserClaimValue(username, claimUri, null);
     }
 
     @GET
@@ -167,91 +104,80 @@ public class UserManagementServiceImpl implements UserManagementService {
                             @HeaderParam("If-Modified-Since") String ifModifiedSince) {
         try {
             UserStoreManager userStoreManager = DeviceMgtAPIUtils.getUserStoreManager();
-            if (userStoreManager.isExistingUser(username)) {
-                BasicUserInfo user = new BasicUserInfo();
-                user.setUsername(username);
-                user.setEmailAddress(getClaimValue(username, Constants.USER_CLAIM_EMAIL_ADDRESS));
-                user.setFirstname(getClaimValue(username, Constants.USER_CLAIM_FIRST_NAME));
-                user.setLastname(getClaimValue(username, Constants.USER_CLAIM_LAST_NAME));
-                // Outputting debug message upon successful retrieval of user
-                if (log.isDebugEnabled()) {
-                    log.debug("User by username: " + username + " was found.");
-                }
-                return Response.status(Response.Status.OK).entity(user).build();
-            } else {
-                // Outputting debug message upon trying to remove non-existing user
+            if (!userStoreManager.isExistingUser(username)) {
                 if (log.isDebugEnabled()) {
                     log.debug("User by username: " + username + " does not exist.");
                 }
-                // returning response with bad request state
-                throw new NotFoundException(
-                        new ErrorResponse.ErrorResponseBuilder().setCode(404l).setMessage("User doesn't exist.")
-                                .build());
+                return Response.status(Response.Status.NOT_FOUND).entity(
+                        new ErrorResponse.ErrorResponseBuilder().setMessage(
+                                "User doesn't exist.").build()).build();
             }
+
+            BasicUserInfo user = this.getBasicUserInfo(username);
+            return Response.status(Response.Status.OK).entity(user).build();
         } catch (UserStoreException e) {
-            String msg = "ErrorResponse occurred while retrieving information of the user '" + username + "'";
+            String msg = "Error occurred while retrieving information of the user '" + username + "'";
             log.error(msg, e);
-            throw new UnexpectedServerErrorException(
-                    new ErrorResponse.ErrorResponseBuilder().setCode(500l).setMessage(msg).build());
+            return Response.serverError().entity(
+                    new ErrorResponse.ErrorResponseBuilder().setMessage(msg).build()).build();
         }
     }
 
     @PUT
     @Path("/{username}")
     @Override
-    public Response updateUser(@PathParam("username") String username, UserInfo userWrapper) {
+    public Response updateUser(@PathParam("username") String username, UserInfo userInfo) {
         try {
             UserStoreManager userStoreManager = DeviceMgtAPIUtils.getUserStoreManager();
-            if (userStoreManager.isExistingUser(userWrapper.getUsername())) {
-                Map<String, String> defaultUserClaims =
-                        this.buildDefaultUserClaims(userWrapper.getFirstname(), userWrapper.getLastname(),
-                                userWrapper.getEmailAddress());
-                if (StringUtils.isNotEmpty(userWrapper.getPassword())) {
-                    // Decoding Base64 encoded password
-                    userStoreManager.updateCredentialByAdmin(userWrapper.getUsername(),
-                            userWrapper.getPassword());
-                    log.debug("User credential of username: " + userWrapper.getUsername() + " has been changed");
+            if (!userStoreManager.isExistingUser(userInfo.getUsername())) {
+                if (log.isDebugEnabled()) {
+                    log.debug("User by username: " + userInfo.getUsername() +
+                            " doesn't exists. Therefore, request made to update user was refused.");
                 }
-                List<String> currentRoles = this.getFilteredRoles(userStoreManager, userWrapper.getUsername());
-                List<String> newRoles = Arrays.asList(userWrapper.getRoles());
+                return Response.status(Response.Status.NOT_FOUND).entity(
+                        new ErrorResponse.ErrorResponseBuilder().setMessage("User by username: " +
+                                userInfo.getUsername() + " doesn't  exist.").build()).build();
+            }
 
-                List<String> rolesToAdd = new ArrayList<>(newRoles);
-                List<String> rolesToDelete = new ArrayList<>();
+            Map<String, String> defaultUserClaims =
+                    this.buildDefaultUserClaims(userInfo.getFirstname(), userInfo.getLastname(),
+                            userInfo.getEmailAddress());
+            if (StringUtils.isNotEmpty(userInfo.getPassword())) {
+                // Decoding Base64 encoded password
+                userStoreManager.updateCredentialByAdmin(userInfo.getUsername(),
+                        userInfo.getPassword());
+                log.debug("User credential of username: " + userInfo.getUsername() + " has been changed");
+            }
+            List<String> currentRoles = this.getFilteredRoles(userStoreManager, userInfo.getUsername());
+            List<String> newRoles = Arrays.asList(userInfo.getRoles());
 
-                for (String role : currentRoles) {
-                    if (newRoles.contains(role)) {
-                        rolesToAdd.remove(role);
-                    } else {
-                        rolesToDelete.add(role);
-                    }
-                }
-                rolesToDelete.remove(ROLE_EVERYONE);
-                userStoreManager.updateRoleListOfUser(userWrapper.getUsername(),
-                        rolesToDelete.toArray(new String[rolesToDelete.size()]),
-                        rolesToAdd.toArray(new String[rolesToAdd.size()]));
-                userStoreManager.setUserClaimValues(userWrapper.getUsername(), defaultUserClaims, null);
-                // Outputting debug message upon successful addition of user
-                if (log.isDebugEnabled()) {
-                    log.debug("User by username: " + userWrapper.getUsername() + " was successfully updated.");
-                }
-                // returning response with success state
-                return Response.status(Response.Status.CREATED).entity("User by username '" + userWrapper.getUsername() +
-                        "' was successfully updated.").build();
-            } else {
-                if (log.isDebugEnabled()) {
-                    log.debug("User by username: " + userWrapper.getUsername() +
-                            " doesn't exists. Therefore, request made to update user was refused.");
+            List<String> rolesToAdd = new ArrayList<>(newRoles);
+            List<String> rolesToDelete = new ArrayList<>();
+
+            for (String role : currentRoles) {
+                if (newRoles.contains(role)) {
+                    rolesToAdd.remove(role);
+                } else {
+                    rolesToDelete.add(role);
                 }
-                throw new NotFoundException(
-                        new ErrorResponse.ErrorResponseBuilder().setCode(404l).setMessage("User by username: " +
-                                userWrapper.getUsername() + " doesn't  exists. Therefore, request made to update user" +
-                                " was refused.").build());
             }
+            rolesToDelete.remove(ROLE_EVERYONE);
+            userStoreManager.updateRoleListOfUser(userInfo.getUsername(),
+                    rolesToDelete.toArray(new String[rolesToDelete.size()]),
+                    rolesToAdd.toArray(new String[rolesToAdd.size()]));
+            userStoreManager.setUserClaimValues(userInfo.getUsername(), defaultUserClaims, null);
+            // Outputting debug message upon successful addition of user
+            if (log.isDebugEnabled()) {
+                log.debug("User by username: " + userInfo.getUsername() + " was successfully updated.");
+            }
+
+            BasicUserInfo updatedUserInfo = this.getBasicUserInfo(username);
+            return Response.ok().entity(updatedUserInfo).build();
         } catch (UserStoreException e) {
-            String msg = "Exception in trying to update user by username: " + userWrapper.getUsername();
+            String msg = "Error occurred while trying to update user '" + userInfo.getUsername() + "'";
             log.error(msg, e);
-            throw new UnexpectedServerErrorException(
-                    new ErrorResponse.ErrorResponseBuilder().setCode(500l).setMessage(msg).build());
+            return Response.serverError().entity(
+                    new ErrorResponse.ErrorResponseBuilder().setMessage(msg).build()).build();
         }
     }
 
@@ -277,31 +203,25 @@ public class UserManagementServiceImpl implements UserManagementService {
     public Response removeUser(@PathParam("username") String username) {
         try {
             UserStoreManager userStoreManager = DeviceMgtAPIUtils.getUserStoreManager();
-            if (userStoreManager.isExistingUser(username)) {
-                // if user already exists, trying to remove user
-                userStoreManager.deleteUser(username);
-                // Outputting debug message upon successful removal of user
-                if (log.isDebugEnabled()) {
-                    log.debug("User by username: " + username + " was successfully removed.");
-                }
-                // returning response with success state
-                return Response.status(Response.Status.OK).entity("User by username: " + username +
-                        " was successfully removed.").build();
-            } else {
-                // Outputting debug message upon trying to remove non-existing user
+            if (!userStoreManager.isExistingUser(username)) {
                 if (log.isDebugEnabled()) {
                     log.debug("User by username: " + username + " does not exist for removal.");
                 }
-                // returning response with bad request state
-                throw new NotFoundException(
-                        new ErrorResponse.ErrorResponseBuilder().setCode(404l).setMessage("User by username: " +
-                                username + " does not exist for removal.").build());
+                return Response.status(Response.Status.NOT_FOUND).entity(
+                        new ErrorResponse.ErrorResponseBuilder().setMessage("User '" +
+                                username + "' does not exist for removal.").build()).build();
             }
+
+            userStoreManager.deleteUser(username);
+            if (log.isDebugEnabled()) {
+                log.debug("User '" + username + "' was successfully removed.");
+            }
+            return Response.status(Response.Status.OK).build();
         } catch (UserStoreException e) {
             String msg = "Exception in trying to remove user by username: " + username;
             log.error(msg, e);
-            throw new UnexpectedServerErrorException(
-                    new ErrorResponse.ErrorResponseBuilder().setCode(500l).setMessage(msg).build());
+            return Response.serverError().entity(
+                    new ErrorResponse.ErrorResponseBuilder().setMessage(msg).build()).build();
         }
     }
 
@@ -311,24 +231,23 @@ public class UserManagementServiceImpl implements UserManagementService {
     public Response getRolesOfUser(@PathParam("username") String username) {
         try {
             UserStoreManager userStoreManager = DeviceMgtAPIUtils.getUserStoreManager();
-            if (userStoreManager.isExistingUser(username)) {
-                RoleList result = new RoleList();
-                result.setList(getFilteredRoles(userStoreManager, username));
-                return Response.status(Response.Status.OK).entity(result).build();
-            } else {
-                // Outputting debug message upon trying to remove non-existing user
+            if (!userStoreManager.isExistingUser(username)) {
                 if (log.isDebugEnabled()) {
                     log.debug("User by username: " + username + " does not exist for role retrieval.");
                 }
-                throw new NotFoundException(
-                        new ErrorResponse.ErrorResponseBuilder().setCode(404l).setMessage("User by username: " + username +
-                                " does not exist for role retrieval.").build());
+                return Response.status(Response.Status.NOT_FOUND).entity(
+                        new ErrorResponse.ErrorResponseBuilder().setMessage("User by username: " + username +
+                                " does not exist for role retrieval.").build()).build();
             }
+
+            RoleList result = new RoleList();
+            result.setList(getFilteredRoles(userStoreManager, username));
+            return Response.status(Response.Status.OK).entity(result).build();
         } catch (UserStoreException e) {
-            String msg = "Exception in trying to retrieve roles for user by username: " + username;
+            String msg = "Error occurred while trying to retrieve roles of the user '" + username + "'";
             log.error(msg, e);
-            throw new UnexpectedServerErrorException(
-                    new ErrorResponse.ErrorResponseBuilder().setCode(500l).setMessage(msg).build());
+            return Response.serverError().entity(
+                    new ErrorResponse.ErrorResponseBuilder().setMessage(msg).build()).build();
         }
     }
 
@@ -342,7 +261,7 @@ public class UserManagementServiceImpl implements UserManagementService {
         }
         List<BasicUserInfo> userList, offsetList;
         String appliedFilter = ((filter == null) || filter.isEmpty() ? "*" : filter);
-        int appliedLimit =  (limit <= 0) ? -1 : (limit + offset);
+        int appliedLimit = (limit <= 0) ? -1 : (limit + offset);
 
         try {
             UserStoreManager userStoreManager = DeviceMgtAPIUtils.getUserStoreManager();
@@ -371,10 +290,10 @@ public class UserManagementServiceImpl implements UserManagementService {
 
             return Response.status(Response.Status.OK).entity(result).build();
         } catch (UserStoreException e) {
-            String msg = "ErrorResponse occurred while retrieving the list of users.";
+            String msg = "Error occurred while retrieving the list of users.";
             log.error(msg, e);
-            throw new UnexpectedServerErrorException(
-                    new ErrorResponse.ErrorResponseBuilder().setCode(500l).setMessage(msg).build());
+            return Response.serverError().entity(
+                    new ErrorResponse.ErrorResponseBuilder().setMessage(msg).build()).build();
         }
     }
 
@@ -407,8 +326,8 @@ public class UserManagementServiceImpl implements UserManagementService {
         } catch (UserStoreException e) {
             String msg = "Error occurred while retrieving the list of users using the filter : " + filter;
             log.error(msg, e);
-            throw new UnexpectedServerErrorException(
-                    new ErrorResponse.ErrorResponseBuilder().setCode(500l).setMessage(msg).build());
+            return Response.serverError().entity(
+                    new ErrorResponse.ErrorResponseBuilder().setMessage(msg).build()).build();
         }
     }
 
@@ -419,4 +338,49 @@ public class UserManagementServiceImpl implements UserManagementService {
         return CredentialManagementResponseBuilder.buildChangePasswordResponse(username, credentials);
     }
 
+    private Map<String, String> buildDefaultUserClaims(String firstName, String lastName, String emailAddress) {
+        Map<String, String> defaultUserClaims = new HashMap<>();
+        defaultUserClaims.put(Constants.USER_CLAIM_FIRST_NAME, firstName);
+        defaultUserClaims.put(Constants.USER_CLAIM_LAST_NAME, lastName);
+        defaultUserClaims.put(Constants.USER_CLAIM_EMAIL_ADDRESS, emailAddress);
+        if (log.isDebugEnabled()) {
+            log.debug("Default claim map is created for new user: " + defaultUserClaims.toString());
+        }
+        return defaultUserClaims;
+    }
+
+    private String generateInitialUserPassword() {
+        int passwordLength = 6;
+        //defining the pool of characters to be used for initial password generation
+        String lowerCaseCharset = "abcdefghijklmnopqrstuvwxyz";
+        String upperCaseCharset = "ABCDEFGHIJKLMNOPQRSTUVWXYZ";
+        String numericCharset = "0123456789";
+        Random randomGenerator = new Random();
+        String totalCharset = lowerCaseCharset + upperCaseCharset + numericCharset;
+        int totalCharsetLength = totalCharset.length();
+        StringBuilder initialUserPassword = new StringBuilder();
+        for (int i = 0; i < passwordLength; i++) {
+            initialUserPassword.append(
+                    totalCharset.charAt(randomGenerator.nextInt(totalCharsetLength)));
+        }
+        if (log.isDebugEnabled()) {
+            log.debug("Initial user password is created for new user: " + initialUserPassword);
+        }
+        return initialUserPassword.toString();
+    }
+
+    private BasicUserInfo getBasicUserInfo(String username) throws UserStoreException {
+        BasicUserInfo userInfo = new BasicUserInfo();
+        userInfo.setUsername(username);
+        userInfo.setEmailAddress(getClaimValue(username, Constants.USER_CLAIM_EMAIL_ADDRESS));
+        userInfo.setFirstname(getClaimValue(username, Constants.USER_CLAIM_FIRST_NAME));
+        userInfo.setLastname(getClaimValue(username, Constants.USER_CLAIM_LAST_NAME));
+        return userInfo;
+    }
+
+    private String getClaimValue(String username, String claimUri) throws UserStoreException {
+        UserStoreManager userStoreManager = DeviceMgtAPIUtils.getUserStoreManager();
+        return userStoreManager.getUserClaimValue(username, claimUri, null);
+    }
+
 }
diff --git a/components/device-mgt/org.wso2.carbon.device.mgt.api/src/main/java/org/wso2/carbon/device/mgt/jaxrs/service/impl/admin/ApplicationManagementAdminServiceImpl.java b/components/device-mgt/org.wso2.carbon.device.mgt.api/src/main/java/org/wso2/carbon/device/mgt/jaxrs/service/impl/admin/ApplicationManagementAdminServiceImpl.java
index 3aa0e8f3c9..59f32534c9 100644
--- a/components/device-mgt/org.wso2.carbon.device.mgt.api/src/main/java/org/wso2/carbon/device/mgt/jaxrs/service/impl/admin/ApplicationManagementAdminServiceImpl.java
+++ b/components/device-mgt/org.wso2.carbon.device.mgt.api/src/main/java/org/wso2/carbon/device/mgt/jaxrs/service/impl/admin/ApplicationManagementAdminServiceImpl.java
@@ -29,9 +29,7 @@ import org.wso2.carbon.device.mgt.common.operation.mgt.Operation;
 import org.wso2.carbon.device.mgt.jaxrs.beans.ErrorResponse;
 import org.wso2.carbon.device.mgt.jaxrs.exception.UnknownApplicationTypeException;
 import org.wso2.carbon.device.mgt.jaxrs.service.api.admin.ApplicationManagementAdminService;
-import org.wso2.carbon.device.mgt.jaxrs.service.impl.util.InputValidationException;
 import org.wso2.carbon.device.mgt.jaxrs.service.impl.util.RequestValidationUtil;
-import org.wso2.carbon.device.mgt.jaxrs.service.impl.util.UnexpectedServerErrorException;
 import org.wso2.carbon.device.mgt.jaxrs.util.DeviceMgtAPIUtils;
 import org.wso2.carbon.device.mgt.jaxrs.util.MDMAndroidOperationUtil;
 import org.wso2.carbon.device.mgt.jaxrs.util.MDMIOSOperationUtil;
@@ -82,21 +80,22 @@ public class ApplicationManagementAdminServiceImpl implements ApplicationManagem
                         applicationWrapper.getDeviceIdentifiers().size() > 0) {
                     activity = appManagerConnector.installApplicationForDevices(operation, applicationWrapper.getDeviceIdentifiers());
                 } else {
-                    throw new InputValidationException(new ErrorResponse.ErrorResponseBuilder().setCode(400l).setMessage(
-                            "No application installation criteria i.e. user/role/device is given").build());
+                    return Response.status(Response.Status.BAD_REQUEST).entity(
+                            new ErrorResponse.ErrorResponseBuilder().setMessage(
+                                    "No application installation criteria i.e. user/role/device is given").build()).build();
                 }
             }
             return Response.status(Response.Status.ACCEPTED).entity(activity).build();
         } catch (ApplicationManagementException e) {
-            String msg = "ErrorResponse occurred while processing application installation request";
+            String msg = "Error occurred while processing application installation request";
             log.error(msg, e);
-            throw new UnexpectedServerErrorException(
-                    new ErrorResponse.ErrorResponseBuilder().setCode(500l).setMessage(msg).build());
+            return Response.serverError().entity(
+                    new ErrorResponse.ErrorResponseBuilder().setMessage(msg).build()).build();
         } catch (UnknownApplicationTypeException e) {
             String msg = "The type of application requested to be installed is not supported";
             log.error(msg, e);
-            throw new UnexpectedServerErrorException(
-                    new ErrorResponse.ErrorResponseBuilder().setCode(500l).setMessage(msg).build());
+            return Response.serverError().entity(
+                    new ErrorResponse.ErrorResponseBuilder().setMessage(msg).build()).build();
         }
     }
 
@@ -130,22 +129,22 @@ public class ApplicationManagementAdminServiceImpl implements ApplicationManagem
                         applicationWrapper.getDeviceIdentifiers().size() > 0) {
                     activity = appManagerConnector.installApplicationForDevices(operation, applicationWrapper.getDeviceIdentifiers());
                 } else {
-                    throw new InputValidationException(
-                            new ErrorResponse.ErrorResponseBuilder().setCode(400l).setMessage(
-                            "No application un-installation criteria i.e. user/role/device is given").build());
+                    return Response.status(Response.Status.BAD_REQUEST).entity(
+                            new ErrorResponse.ErrorResponseBuilder().setMessage(
+                                    "No application un-installation criteria i.e. user/role/device is given").build()).build();
                 }
             }
             return Response.status(Response.Status.ACCEPTED).entity(activity).build();
         } catch (ApplicationManagementException e) {
-            String msg = "ErrorResponse occurred while processing application un-installation request";
+            String msg = "Error occurred while processing application un-installation request";
             log.error(msg, e);
-            throw new UnexpectedServerErrorException(
-                    new ErrorResponse.ErrorResponseBuilder().setCode(500l).setMessage(msg).build());
+            return Response.serverError().entity(
+                    new ErrorResponse.ErrorResponseBuilder().setMessage(msg).build()).build();
         } catch (UnknownApplicationTypeException e) {
             String msg = "The type of application requested to be un-installed is not supported";
             log.error(msg, e);
-            throw new UnexpectedServerErrorException(
-                    new ErrorResponse.ErrorResponseBuilder().setCode(500l).setMessage(msg).build());
+            return Response.serverError().entity(
+                    new ErrorResponse.ErrorResponseBuilder().setMessage(msg).build()).build();
         }
     }
 
diff --git a/components/device-mgt/org.wso2.carbon.device.mgt.api/src/main/java/org/wso2/carbon/device/mgt/jaxrs/service/impl/admin/DeviceManagementAdminServiceImpl.java b/components/device-mgt/org.wso2.carbon.device.mgt.api/src/main/java/org/wso2/carbon/device/mgt/jaxrs/service/impl/admin/DeviceManagementAdminServiceImpl.java
index 589127b211..4956583627 100644
--- a/components/device-mgt/org.wso2.carbon.device.mgt.api/src/main/java/org/wso2/carbon/device/mgt/jaxrs/service/impl/admin/DeviceManagementAdminServiceImpl.java
+++ b/components/device-mgt/org.wso2.carbon.device.mgt.api/src/main/java/org/wso2/carbon/device/mgt/jaxrs/service/impl/admin/DeviceManagementAdminServiceImpl.java
@@ -28,8 +28,6 @@ import org.wso2.carbon.device.mgt.common.DeviceManagementException;
 import org.wso2.carbon.device.mgt.jaxrs.beans.DeviceList;
 import org.wso2.carbon.device.mgt.jaxrs.beans.ErrorResponse;
 import org.wso2.carbon.device.mgt.jaxrs.service.api.admin.DeviceManagementAdminService;
-import org.wso2.carbon.device.mgt.jaxrs.service.impl.util.*;
-import org.wso2.carbon.device.mgt.jaxrs.service.impl.util.NotFoundException;
 import org.wso2.carbon.device.mgt.jaxrs.util.DeviceMgtAPIUtils;
 
 import javax.ws.rs.*;
@@ -55,21 +53,16 @@ public class DeviceManagementAdminServiceImpl implements DeviceManagementAdminSe
         try {
             int currentTenantId = CarbonContext.getThreadLocalCarbonContext().getTenantId();
             if (MultitenantConstants.SUPER_TENANT_ID != currentTenantId) {
-                throw new UnauthorizedAccessException(
-                    new ErrorResponse.ErrorResponseBuilder().setCode(401l).setMessage(
-                        "Current logged in user is not authorized to perform this operation").build());
+                return Response.status(Response.Status.UNAUTHORIZED).entity(
+                        new ErrorResponse.ErrorResponseBuilder().setMessage(
+                                "Current logged in user is not authorized to perform this operation").build()).build();
             }
             PrivilegedCarbonContext.startTenantFlow();
             PrivilegedCarbonContext.getThreadLocalCarbonContext().setTenantDomain(tenantDomain);
             PrivilegedCarbonContext.getThreadLocalCarbonContext().setTenantId(DeviceMgtAPIUtils.getTenantId(tenantDomain));
 
             List<Device> devices = DeviceMgtAPIUtils.getDeviceManagementService().
-                getDevicesByNameAndType(name, type, offset, limit);
-            if (devices == null || devices.size() == 0) {
-                throw new NotFoundException(
-                        new ErrorResponse.ErrorResponseBuilder().setCode(404l).setMessage("No device, which carries" +
-                                " the name '" + name + "', is currently enrolled in the system").build());
-            }
+                    getDevicesByNameAndType(name, type, offset, limit);
 
             // setting up paginated result
             DeviceList deviceList = new DeviceList();
@@ -80,8 +73,8 @@ public class DeviceManagementAdminServiceImpl implements DeviceManagementAdminSe
         } catch (DeviceManagementException e) {
             String msg = "Error occurred at server side while fetching device list.";
             log.error(msg, e);
-            throw new UnexpectedServerErrorException(
-                new ErrorResponse.ErrorResponseBuilder().setCode(500l).setMessage(msg).build());
+            return Response.serverError().entity(
+                    new ErrorResponse.ErrorResponseBuilder().setMessage(msg).build()).build();
         } finally {
             PrivilegedCarbonContext.endTenantFlow();
         }
diff --git a/components/device-mgt/org.wso2.carbon.device.mgt.api/src/main/java/org/wso2/carbon/device/mgt/jaxrs/service/impl/util/RequestValidationUtil.java b/components/device-mgt/org.wso2.carbon.device.mgt.api/src/main/java/org/wso2/carbon/device/mgt/jaxrs/service/impl/util/RequestValidationUtil.java
index f4defbdfad..5d0a585ca7 100644
--- a/components/device-mgt/org.wso2.carbon.device.mgt.api/src/main/java/org/wso2/carbon/device/mgt/jaxrs/service/impl/util/RequestValidationUtil.java
+++ b/components/device-mgt/org.wso2.carbon.device.mgt.api/src/main/java/org/wso2/carbon/device/mgt/jaxrs/service/impl/util/RequestValidationUtil.java
@@ -304,8 +304,8 @@ public class RequestValidationUtil {
         }
     }
 
-    public static void validateRoleDetails(RoleWrapper roleWrapper) {
-        if (roleWrapper == null) {
+    public static void validateRoleDetails(RoleInfo roleInfo) {
+        if (roleInfo == null) {
             throw new InputValidationException(
                     new ErrorResponse.ErrorResponseBuilder().setCode(400l).setMessage("Request body is incorrect or" +
                             " empty").build());
diff --git a/components/device-mgt/org.wso2.carbon.device.mgt.api/src/main/java/org/wso2/carbon/device/mgt/jaxrs/swagger/extension/SecurityDefinitionConfigurator.java b/components/device-mgt/org.wso2.carbon.device.mgt.api/src/main/java/org/wso2/carbon/device/mgt/jaxrs/swagger/extension/SecurityDefinitionConfigurator.java
new file mode 100644
index 0000000000..2ad4b54aa5
--- /dev/null
+++ b/components/device-mgt/org.wso2.carbon.device.mgt.api/src/main/java/org/wso2/carbon/device/mgt/jaxrs/swagger/extension/SecurityDefinitionConfigurator.java
@@ -0,0 +1,58 @@
+/*
+ *   Copyright (c) 2016, WSO2 Inc. (http://www.wso2.org) All Rights Reserved.
+ *
+ *   WSO2 Inc. licenses this file to you under the Apache License,
+ *   Version 2.0 (the "License"); you may not use this file except
+ *   in compliance with the License.
+ *   You may obtain a copy of the License at
+ *
+ *   http://www.apache.org/licenses/LICENSE-2.0
+ *
+ *   Unless required by applicable law or agreed to in writing,
+ *   software distributed under the License is distributed on an
+ *   "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
+ *   KIND, either express or implied.  See the License for the
+ *   specific language governing permissions and limitations
+ *   under the License.
+ *
+ */
+package org.wso2.carbon.device.mgt.jaxrs.swagger.extension;
+
+import io.swagger.annotations.SwaggerDefinition;
+import io.swagger.jaxrs.Reader;
+import io.swagger.jaxrs.config.ReaderListener;
+import io.swagger.models.Swagger;
+import io.swagger.models.auth.OAuth2Definition;
+import io.swagger.models.auth.SecuritySchemeDefinition;
+
+import java.util.HashMap;
+import java.util.Map;
+
+@SwaggerDefinition(
+        basePath = "/api/device-mgt/v1.0",
+        host = "localhost:9443"
+)
+public class SecurityDefinitionConfigurator implements ReaderListener {
+
+    public static final String TOKEN_AUTH_SCHEME = "tokenAuthScheme";
+
+    @Override
+    public void beforeScan(Reader reader, Swagger swagger) {
+
+    }
+
+    @Override
+    public void afterScan(Reader reader, Swagger swagger) {
+        OAuth2Definition tokenScheme = new OAuth2Definition();
+        tokenScheme.setType("oauth2");
+        tokenScheme.setFlow("password");
+        tokenScheme.setTokenUrl("https://" + swagger.getHost() + "/oauth/token");
+        tokenScheme.setAuthorizationUrl("https://" + swagger.getHost() + "/oauth/authorize");
+
+        Map<String, SecuritySchemeDefinition> schemes = new HashMap<>();
+        schemes.put(TOKEN_AUTH_SCHEME, tokenScheme);
+
+        swagger.setSecurityDefinitions(schemes);
+    }
+
+}
diff --git a/components/device-mgt/org.wso2.carbon.device.mgt.api/src/main/java/org/wso2/carbon/device/mgt/jaxrs/util/CredentialManagementResponseBuilder.java b/components/device-mgt/org.wso2.carbon.device.mgt.api/src/main/java/org/wso2/carbon/device/mgt/jaxrs/util/CredentialManagementResponseBuilder.java
index 6fe5706243..09371c3c5d 100644
--- a/components/device-mgt/org.wso2.carbon.device.mgt.api/src/main/java/org/wso2/carbon/device/mgt/jaxrs/util/CredentialManagementResponseBuilder.java
+++ b/components/device-mgt/org.wso2.carbon.device.mgt.api/src/main/java/org/wso2/carbon/device/mgt/jaxrs/util/CredentialManagementResponseBuilder.java
@@ -21,11 +21,9 @@ package org.wso2.carbon.device.mgt.jaxrs.util;
 import org.apache.commons.logging.Log;
 import org.apache.commons.logging.LogFactory;
 import org.wso2.carbon.device.mgt.jaxrs.beans.ErrorResponse;
-import org.wso2.carbon.device.mgt.jaxrs.beans.PasswordResetWrapper;
 import org.wso2.carbon.device.mgt.jaxrs.beans.OldPasswordResetWrapper;
-import org.wso2.carbon.device.mgt.jaxrs.service.impl.util.InputValidationException;
+import org.wso2.carbon.device.mgt.jaxrs.beans.PasswordResetWrapper;
 import org.wso2.carbon.device.mgt.jaxrs.service.impl.util.RequestValidationUtil;
-import org.wso2.carbon.device.mgt.jaxrs.service.impl.util.UnexpectedServerErrorException;
 import org.wso2.carbon.user.api.UserStoreException;
 import org.wso2.carbon.user.api.UserStoreManager;
 
@@ -44,7 +42,8 @@ public class CredentialManagementResponseBuilder {
 
     /**
      * Builds the response to change the password of a user
-     * @param username - Username of the user.
+     *
+     * @param username    - Username of the user.
      * @param credentials - User credentials
      * @return Response Object
      */
@@ -52,38 +51,39 @@ public class CredentialManagementResponseBuilder {
         try {
             UserStoreManager userStoreManager = DeviceMgtAPIUtils.getUserStoreManager();
             if (!userStoreManager.isExistingUser(username)) {
-                throw new InputValidationException(
-                        new ErrorResponse.ErrorResponseBuilder().setCode(400l).setMessage("No user found with the username "
-                                + username).build());
+                return Response.status(Response.Status.NOT_FOUND).entity(
+                        new ErrorResponse.ErrorResponseBuilder().setMessage("No user found with the username '"
+                                + username + "'").build()).build();
             }
             RequestValidationUtil.validateCredentials(credentials);
 
             if (!validateCredential(credentials.getNewPassword())) {
                 String errorMsg = DeviceMgtAPIUtils.getRealmService().getBootstrapRealmConfiguration()
                         .getUserStoreProperty(PASSWORD_VALIDATION_ERROR_MSG_TAG);
-                throw new InputValidationException(
-                        new ErrorResponse.ErrorResponseBuilder().setCode(400l).setMessage(errorMsg).build());
+                return Response.status(Response.Status.BAD_REQUEST).entity(
+                        new ErrorResponse.ErrorResponseBuilder().setMessage(errorMsg).build()).build();
             }
             userStoreManager.updateCredential(username, credentials.getNewPassword(),
-                                              credentials.getOldPassword());
+                    credentials.getOldPassword());
             return Response.status(Response.Status.OK).entity("UserImpl password by username: " +
                     username + " was successfully changed.").build();
         } catch (UserStoreException e) {
             log.error(e.getMessage(), e);
-            throw new UnexpectedServerErrorException(
-                    new ErrorResponse.ErrorResponseBuilder().setCode(500l).setMessage(e.getMessage()).build());
+            return Response.serverError().entity(
+                    new ErrorResponse.ErrorResponseBuilder().setMessage(e.getMessage()).build()).build();
         } catch (UnsupportedEncodingException e) {
             String msg = "Could not change the password of the user: " + username +
                     ". The Character Encoding is not supported.";
             log.error(msg, e);
-            throw new UnexpectedServerErrorException(
-                    new ErrorResponse.ErrorResponseBuilder().setCode(500l).setMessage(msg).build());
+            return Response.serverError().entity(
+                    new ErrorResponse.ErrorResponseBuilder().setMessage(msg).build()).build();
         }
     }
 
     /**
      * Builds the response to reset the password of a user
-     * @param username - Username of the user.
+     *
+     * @param username    - Username of the user.
      * @param credentials - User credentials
      * @return Response Object
      */
@@ -91,35 +91,35 @@ public class CredentialManagementResponseBuilder {
         try {
             UserStoreManager userStoreManager = DeviceMgtAPIUtils.getUserStoreManager();
             if (!userStoreManager.isExistingUser(username)) {
-                throw new InputValidationException(
-                        new ErrorResponse.ErrorResponseBuilder().setCode(400l).setMessage("No user found with the username "
-                                + username).build());
+                return Response.status(Response.Status.BAD_REQUEST).entity(
+                        new ErrorResponse.ErrorResponseBuilder().setMessage("No user found with the username "
+                                + username).build()).build();
             }
             if (credentials == null || credentials.getNewPassword() == null) {
-                throw new InputValidationException(
-                        new ErrorResponse.ErrorResponseBuilder().setCode(400l).setMessage("Password cannot be empty."
-                                + username).build());
+                return Response.status(Response.Status.BAD_REQUEST).entity(
+                        new ErrorResponse.ErrorResponseBuilder().setMessage("Password cannot be empty."
+                                + username).build()).build();
             }
             if (!validateCredential(credentials.getNewPassword())) {
                 String errorMsg = DeviceMgtAPIUtils.getRealmService().getBootstrapRealmConfiguration()
                         .getUserStoreProperty(PASSWORD_VALIDATION_ERROR_MSG_TAG);
-                throw new InputValidationException(
-                        new ErrorResponse.ErrorResponseBuilder().setCode(400l).setMessage(errorMsg).build());
+                return Response.status(Response.Status.BAD_REQUEST).entity(
+                        new ErrorResponse.ErrorResponseBuilder().setMessage(errorMsg).build()).build();
             }
             userStoreManager.updateCredentialByAdmin(username, credentials.getNewPassword());
             return Response.status(Response.Status.OK).entity("UserImpl password by username: " +
                     username + " was successfully changed.").build();
         } catch (UserStoreException e) {
-            String msg = "ErrorResponse occurred while updating the credentials of user '" + username + "'";
+            String msg = "Error occurred while updating the credentials of user '" + username + "'";
             log.error(msg, e);
-            throw new UnexpectedServerErrorException(
-                    new ErrorResponse.ErrorResponseBuilder().setCode(500l).setMessage(msg).build());
+            return Response.serverError().entity(
+                    new ErrorResponse.ErrorResponseBuilder().setMessage(msg).build()).build();
         } catch (UnsupportedEncodingException e) {
             String msg = "Could not change the password of the user: " + username +
                     ". The Character Encoding is not supported.";
             log.error(msg, e);
-            throw new UnexpectedServerErrorException(
-                    new ErrorResponse.ErrorResponseBuilder().setCode(500l).setMessage(msg).build());
+            return Response.serverError().entity(
+                    new ErrorResponse.ErrorResponseBuilder().setMessage(msg).build()).build();
         }
     }
 
diff --git a/components/policy-mgt/org.wso2.carbon.policy.mgt.core/src/main/java/org/wso2/carbon/policy/mgt/core/internal/PolicyManagementServiceComponent.java b/components/policy-mgt/org.wso2.carbon.policy.mgt.core/src/main/java/org/wso2/carbon/policy/mgt/core/internal/PolicyManagementServiceComponent.java
index 13711f43b0..0c456fce28 100644
--- a/components/policy-mgt/org.wso2.carbon.policy.mgt.core/src/main/java/org/wso2/carbon/policy/mgt/core/internal/PolicyManagementServiceComponent.java
+++ b/components/policy-mgt/org.wso2.carbon.policy.mgt.core/src/main/java/org/wso2/carbon/policy/mgt/core/internal/PolicyManagementServiceComponent.java
@@ -91,7 +91,7 @@ public class PolicyManagementServiceComponent {
                     DeviceConfigurationManager.getInstance().getDeviceManagementConfig().getPolicyConfiguration();
             if(policyConfiguration.getMonitoringEnable()) {
                 TaskScheduleService taskScheduleService = new TaskScheduleServiceImpl();
-                taskScheduleService.startTask(PolicyManagerUtil.getMonitoringFequency());
+                taskScheduleService.startTask(PolicyManagerUtil.getMonitoringFrequency());
             }
 
         } catch (Throwable t) {
diff --git a/components/policy-mgt/org.wso2.carbon.policy.mgt.core/src/main/java/org/wso2/carbon/policy/mgt/core/util/PolicyManagerUtil.java b/components/policy-mgt/org.wso2.carbon.policy.mgt.core/src/main/java/org/wso2/carbon/policy/mgt/core/util/PolicyManagerUtil.java
index c0e587b857..0d80901d21 100644
--- a/components/policy-mgt/org.wso2.carbon.policy.mgt.core/src/main/java/org/wso2/carbon/policy/mgt/core/util/PolicyManagerUtil.java
+++ b/components/policy-mgt/org.wso2.carbon.policy.mgt.core/src/main/java/org/wso2/carbon/policy/mgt/core/util/PolicyManagerUtil.java
@@ -196,7 +196,7 @@ public class PolicyManagerUtil {
     }
 
 
-    public static int getMonitoringFequency() throws PolicyManagementException {
+    public static int getMonitoringFrequency() throws PolicyManagementException {
 
         PlatformConfigurationManagementService configMgtService = new PlatformConfigurationManagementServiceImpl();
         PlatformConfiguration tenantConfiguration;