Change API to filter devices using a given OS version

When syncing devices a value will be generated for each device version.
At the API call same method is used to generate a value for the passed
OS version then thedevices are filtered using those 2 values.

This will still create a similar value but now will use
mathematical operations(pow operations) to generate

components/device-mgt/org.wso2.carbon.device.mgt.api/src/main/java/org/wso2/carbon/device/mgt/jaxrs/service/api/ReportManagementService.java

@@ -313,12 +313,12 @@ public interface ReportManagementService {
                     int limit) throws ReportManagementException;
 
     @GET
-    @Path("expired-devices/{deviceType}")
+    @Path("/expired-devices/{deviceType}")
     @ApiOperation(
             produces = MediaType.APPLICATION_JSON,
             httpMethod = "GET",
-            value = "Getting Details of Registered Devices filtered by OS version build date",
+            value = "Getting Details of Registered Devices filtered by OS version",
-            notes = "Provides details of devices that have a version build date older than the provided date.",
+            notes = "Provides details of devices that have a OS version older than the provided version.",
             tags = "Device Management",
             extensions = {
                     @Extension(properties = {
@@ -337,9 +337,9 @@ public interface ReportManagementService {
                                             name = "Content-Type",
                                             description = "The content type of the body")}),
                     @ApiResponse(
-                            code = 404,
+                            code = 400,
-                            message = "Not Found. " +
+                            message = "Bad Request. " +
-                                      "\n Device type does not exist",
+                                      "\n Contents of the request are invalid",
                             response = ErrorResponse.class),
                     @ApiResponse(
                             code = 500,
@@ -354,10 +354,10 @@ public interface ReportManagementService {
                     required = true)
             @PathParam("deviceType") String deviceType,
             @ApiParam(
-                    name = "osBuildDate",
+                    name = "osVersion",
-                    value = "Minimum OS version build date which is used to filter the devices.",
+                    value = "Minimum OS version which is used to filter the devices.",
                     required = true)
-            @QueryParam("osBuildDate") Long osBuildDate,
+            @QueryParam("osVersion") String osVersion,
             @ApiParam(
                     name = "offset",
                     value = "The starting pagination index for the list of filtered devices.",

components/device-mgt/org.wso2.carbon.device.mgt.api/src/main/java/org/wso2/carbon/device/mgt/jaxrs/service/impl/ReportManagementServiceImpl.java

@@ -25,6 +25,7 @@ import org.apache.commons.logging.LogFactory;
 import org.wso2.carbon.device.mgt.common.Device;
 import org.wso2.carbon.device.mgt.common.PaginationRequest;
 import org.wso2.carbon.device.mgt.common.PaginationResult;
+import org.wso2.carbon.device.mgt.common.exceptions.BadRequestException;
 import org.wso2.carbon.device.mgt.common.exceptions.DeviceTypeNotFoundException;
 import org.wso2.carbon.device.mgt.common.exceptions.ReportManagementException;
 import org.wso2.carbon.device.mgt.core.report.mgt.Constants;
@@ -169,10 +170,10 @@ public class ReportManagementServiceImpl implements ReportManagementService {
     }
 
     @GET
-    @Path("expired-devices/{deviceType}")
+    @Path("/expired-devices/{deviceType}")
     @Override
     public Response getExpiredDevicesByOSVersion(@PathParam("deviceType") String deviceType,
-                                                 @QueryParam("osBuildDate") Long osBuildDate,
+                                                 @QueryParam("osVersion") String osVersion,
                                                  @DefaultValue("0")
                                                  @QueryParam("offset") int offset,
                                                  @DefaultValue("5")
@@ -180,20 +181,23 @@ public class ReportManagementServiceImpl implements ReportManagementService {
         try {
             PaginationRequest request = new PaginationRequest(offset, limit);
             request.setDeviceType(deviceType);
-            request.setProperty(Constants.OS_BUILD_DATE, osBuildDate);
+            request.setProperty(Constants.OS_VERSION, osVersion);
 
             PaginationResult paginationResult = DeviceMgtAPIUtils
                     .getReportManagementService()
                     .getDevicesExpiredByOSVersion(request);
 
-            return Response.status(Response.Status.OK).entity(paginationResult).build();
+            DeviceList devices = new DeviceList();
-        } catch (DeviceTypeNotFoundException e) {
+            devices.setList((List<Device>) paginationResult.getData());
-            String msg = "Error occurred while retrieving devices list. Device type: " + deviceType +
+            devices.setCount(paginationResult.getRecordsTotal());
-                         "is not valid";
+
-            log.error(msg);
+            return Response.status(Response.Status.OK).entity(devices).build();
-            return Response.status(Response.Status.NOT_FOUND).entity(msg).build();
+        } catch (BadRequestException e) {
+            String msg = "Error occurred while validating device type or the OS version.";
+            log.error(msg, e);
+            return Response.status(Response.Status.BAD_REQUEST).entity(msg).build();
         } catch (ReportManagementException e) {
-            String msg = "Error occurred while retrieving devices list with out-dated OS build versions";
+            String msg = "Error occurred while retrieving list of devices with out-dated OS versions.";
             log.error(msg, e);
             return Response.status(Response.Status.INTERNAL_SERVER_ERROR).entity(msg).build();
         }

components/device-mgt/org.wso2.carbon.device.mgt.common/src/main/java/org/wso2/carbon/device/mgt/common/exceptions/BadRequestException.java

@@ -0,0 +1,46 @@
+/*
+ *
+ *  Copyright (c) 2020, Entgra (pvt) Ltd. (http://entgra.io) All Rights Reserved.
+ *
+ *  Entgra (pvt) Ltd. 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.common.exceptions;
+
+public class BadRequestException extends Exception {
+    private static final long serialVersionUID = 2304023531260840549L;
+
+    public BadRequestException() {
+        super();
+    }
+
+    public BadRequestException(String msg) {
+        super(msg);
+    }
+
+    public BadRequestException(Throwable cause) {
+        super(cause);
+    }
+
+    public BadRequestException(String msg, Exception nestedEx) {
+        super(msg, nestedEx);
+    }
+
+    public BadRequestException(String message, Throwable cause) {
+        super(message, cause);
+    }
+
+}

components/device-mgt/org.wso2.carbon.device.mgt.common/src/main/java/org/wso2/carbon/device/mgt/common/report/mgt/ReportManagementService.java

@@ -21,6 +21,7 @@ import com.google.gson.JsonObject;
 import org.wso2.carbon.device.mgt.common.PaginationRequest;
 import org.wso2.carbon.device.mgt.common.PaginationResult;
 import org.wso2.carbon.device.mgt.common.app.mgt.ApplicationManagementException;
+import org.wso2.carbon.device.mgt.common.exceptions.BadRequestException;
 import org.wso2.carbon.device.mgt.common.exceptions.DeviceTypeNotFoundException;
 import org.wso2.carbon.device.mgt.common.exceptions.ReportManagementException;
 
@@ -56,10 +57,9 @@ public interface ReportManagementService {
      * @param request {@link PaginationRequest}
      * @return {@link PaginationResult}
      * @throws ReportManagementException Might occur during the business logic or building database query
-     * @throws DeviceTypeNotFoundException Might occur while validating the device type
      */
     PaginationResult getDevicesExpiredByOSVersion(PaginationRequest request)
-            throws ReportManagementException, DeviceTypeNotFoundException;
+            throws ReportManagementException, BadRequestException;
 
     /**
      * Get a paginated list of devices which is filtered by given encryption status

components/device-mgt/org.wso2.carbon.device.mgt.core/src/main/java/org/wso2/carbon/device/mgt/core/dao/DeviceDAO.java

@@ -637,12 +637,12 @@ public interface DeviceDAO {
      * Count the number of devices older than the given OS version of a device type
      *
      * @param deviceType Device type name
-     * @param osBuildDate BUild date off the current OS version
+     * @param osValue Generated value for the OS version
      * @param tenantId Id of the current tenant.
      * @return {@link Integer}
      * @throws DeviceManagementDAOException Thrown if error occurs while database transactions
      */
-    int getCountOfDeviceExpiredByOSVersion(String deviceType, long osBuildDate, int tenantId)
+    int getCountOfDeviceExpiredByOSVersion(String deviceType, Long osValue, int tenantId)
             throws DeviceManagementDAOException;
 
     /**

components/device-mgt/org.wso2.carbon.device.mgt.core/src/main/java/org/wso2/carbon/device/mgt/core/dao/impl/AbstractDeviceDAOImpl.java

@@ -1916,107 +1916,6 @@ public abstract class AbstractDeviceDAOImpl implements DeviceDAO {
         }
     }
     
-    @Override
-    public List<Device> getDevicesExpiredByOSVersion(PaginationRequest request, int tenantId)
-            throws DeviceManagementDAOException {
-        try {
-            Long osBuildDate = (Long) request.getProperty(Constants.OS_BUILD_DATE);
-            Connection conn = getConnection();
-            String sql = "SELECT " +
-                         "dt.NAME AS DEVICE_TYPE, " +
-                         "d.ID AS DEVICE_ID, " +
-                         "d.NAME AS DEVICE_NAME, " +
-                         "d.DESCRIPTION, " +
-                         "d.DEVICE_IDENTIFICATION, " +
-                         "dd.OS_VERSION, " +
-                         "dd.OS_BUILD_DATE, " +
-                         "e.ID AS ENROLMENT_ID, " +
-                         "e.OWNER, " +
-                         "e.OWNERSHIP, " +
-                         "e.STATUS, " +
-                         "e.DATE_OF_LAST_UPDATE, " +
-                         "e.DATE_OF_ENROLMENT " +
-                         "FROM DM_DEVICE d, " +
-                         "DM_DEVICE_DETAIL dd, " +
-                         "DM_ENROLMENT e, " +
-                         "(SELECT ID, NAME " +
-                         "FROM DM_DEVICE_TYPE " +
-                         "WHERE NAME = ? " +
-                         "AND PROVIDER_TENANT_ID = ?) dt " +
-                         "WHERE dt.ID = d.DEVICE_TYPE_ID " +
-                         "AND d.ID = e.DEVICE_ID " +
-                         "AND d.ID = dd.DEVICE_ID " +
-                         "AND dd.OS_BUILD_DATE < ? " +
-                         "LIMIT ? OFFSET ?";
-
-            try (PreparedStatement ps = conn.prepareStatement(sql)) {
-                int paramIDx = 1;
-                ps.setString(paramIDx++, request.getDeviceType());
-                ps.setInt(paramIDx++, tenantId);
-                ps.setLong(paramIDx++, osBuildDate);
-                ps.setInt(paramIDx++, request.getRowCount());
-                ps.setInt(paramIDx, request.getStartIndex());
-
-                try (ResultSet rs = ps.executeQuery()) {
-                    List<Device> devices = new ArrayList<>();
-                    DeviceInfo deviceInfo = new DeviceInfo();
-                    while (rs.next()) {
-                        Device device = DeviceManagementDAOUtil.loadDevice(rs);
-                        deviceInfo.setOsVersion(rs.getString(Constants.OS_VERSION));
-                        deviceInfo.setOsBuildDate(rs.getString(Constants.OS_BUILD_DATE));
-                        device.setDeviceInfo(deviceInfo);
-                        devices.add(device);
-                    }
-                    return devices;
-                }
-            }
-        } catch (SQLException e) {
-            String msg = "Error occurred while building or executing queries to retrieve information " +
-                         "of devices with an older OS build date";
-            log.error(msg, e);
-            throw new DeviceManagementDAOException(msg, e);
-        }
-    }
-
-    @Override
-    public int getCountOfDeviceExpiredByOSVersion(String deviceType, long osBuildDate, int tenantId)
-            throws DeviceManagementDAOException {
-        try {
-            Connection conn = getConnection();
-            String sql = "SELECT " +
-                         "COUNT(dd.DEVICE_ID) AS DEVICE_COUNT " +
-                         "FROM DM_DEVICE d, " +
-                         "DM_DEVICE_DETAIL dd, " +
-                         "(SELECT ID " +
-                         "FROM DM_DEVICE_TYPE " +
-                         "WHERE NAME = ? " +
-                         "AND PROVIDER_TENANT_ID = ?) dt " +
-                         "WHERE d.DEVICE_TYPE_ID = dt.ID " +
-                         "AND d.ID = dd.DEVICE_ID " +
-                         "AND dd.OS_BUILD_DATE < ?";
-
-            try (PreparedStatement ps = conn.prepareStatement(sql)) {
-                int paramIdx = 1;
-                ps.setString(paramIdx++, deviceType);
-                ps.setInt(paramIdx++, tenantId);
-                ps.setLong(paramIdx, osBuildDate);
-
-                try (ResultSet rs = ps.executeQuery()) {
-                    int deviceCount = 0;
-                    if (rs.next()) {
-                        deviceCount = rs.getInt("DEVICE_COUNT");
-                    }
-                    return deviceCount;
-                }
-            }
-        } catch (SQLException e) {
-            String msg = "Error occurred while building or executing queries to retrieve the count " +
-                         "of devices with an older OS build date";
-            log.error(msg, e);
-            throw new DeviceManagementDAOException(msg, e);
-        }
-    }
-
     @Override
     public List<Device> getAppNotInstalledDevices(
             PaginationRequest request, int tenantId, String packageName, String version)

components/device-mgt/org.wso2.carbon.device.mgt.core/src/main/java/org/wso2/carbon/device/mgt/core/dao/impl/device/GenericDeviceDAOImpl.java

@@ -23,11 +23,14 @@ import org.apache.commons.logging.Log;
 import org.apache.commons.logging.LogFactory;
 import org.wso2.carbon.device.mgt.common.Count;
 import org.wso2.carbon.device.mgt.common.Device;
+import org.wso2.carbon.device.mgt.common.DeviceManagementConstants;
 import org.wso2.carbon.device.mgt.common.PaginationRequest;
+import org.wso2.carbon.device.mgt.common.device.details.DeviceInfo;
 import org.wso2.carbon.device.mgt.core.dao.DeviceManagementDAOException;
 import org.wso2.carbon.device.mgt.core.dao.DeviceManagementDAOFactory;
 import org.wso2.carbon.device.mgt.core.dao.impl.AbstractDeviceDAOImpl;
 import org.wso2.carbon.device.mgt.core.dao.util.DeviceManagementDAOUtil;
+import org.wso2.carbon.device.mgt.core.report.mgt.Constants;
 
 import java.sql.Connection;
 import java.sql.PreparedStatement;
@@ -858,6 +861,124 @@ public class GenericDeviceDAOImpl extends AbstractDeviceDAOImpl {
         }
     }
 
+    @Override
+    public List<Device> getDevicesExpiredByOSVersion(PaginationRequest request, int tenantId)
+            throws DeviceManagementDAOException {
+        try {
+            Long osValue = (Long) request.getProperty(Constants.OS_VALUE);
+            Connection conn = getConnection();
+            String dataSourceType = conn.getMetaData().getDatabaseProductName();
+            String sql="SELECT " +
+                       "d1.DEVICE_TYPE, " +
+                       "d1.DEVICE_ID, " +
+                       "d1.DEVICE_NAME, " +
+                       "d1.DESCRIPTION, " +
+                       "d1.DEVICE_IDENTIFICATION, " +
+                       "ddd.OS_VERSION, " +
+                       "e.ID AS ENROLMENT_ID, " +
+                       "e.OWNER, " +
+                       "e.OWNERSHIP, " +
+                       "e.STATUS, " +
+                       "e.DATE_OF_LAST_UPDATE, " +
+                       "e.DATE_OF_ENROLMENT " +
+                       "FROM DM_DEVICE_INFO ddi," +
+                       "DM_DEVICE_DETAIL ddd, " +
+                       "DM_ENROLMENT e, " +
+                       "(SELECT dt.NAME AS DEVICE_TYPE, " +
+                       "d.ID AS DEVICE_ID, " +
+                       "d.NAME AS DEVICE_NAME, " +
+                       "DESCRIPTION, " +
+                       "DEVICE_IDENTIFICATION " +
+                       "FROM DM_DEVICE_TYPE dt, " +
+                       "DM_DEVICE d " +
+                       "WHERE dt.NAME = ? " +
+                       "AND PROVIDER_TENANT_ID = ? " +
+                       "AND dt.ID = d.DEVICE_TYPE_ID " +
+                       ") d1 " +
+                       "WHERE d1.DEVICE_ID = e.DEVICE_ID " +
+                       "AND d1.DEVICE_ID = ddi.DEVICE_ID " +
+                       "AND ddi.KEY_FIELD = ? ";
+            if (dataSourceType.contains(DeviceManagementConstants.DataBaseTypes.DB_TYPE_H2)) {
+                sql += "AND CAST( ddi.VALUE_FIELD AS BIGINT ) < ? ";
+            } else if (dataSourceType.contains(DeviceManagementConstants.DataBaseTypes.DB_TYPE_MYSQL)) {
+                sql += "AND CAST( ddi.VALUE_FIELD AS UNSIGNED ) < ? ";
+            }
+            sql += "LIMIT ? OFFSET ?";
+
+            try (PreparedStatement ps = conn.prepareStatement(sql)) {
+                ps.setString(1, request.getDeviceType());
+                ps.setInt(2, tenantId);
+                ps.setString(3, Constants.OS_VALUE);
+                ps.setLong(4, osValue);
+                ps.setInt(5, request.getRowCount());
+                ps.setInt(6, request.getStartIndex());
+
+                try (ResultSet rs = ps.executeQuery()) {
+                    List<Device> devices = new ArrayList<>();
+                    while (rs.next()) {
+                        Device device = DeviceManagementDAOUtil.loadDevice(rs);
+                        DeviceInfo deviceInfo = new DeviceInfo();
+                        deviceInfo.setOsVersion(rs.getString("OS_VERSION"));
+                        device.setDeviceInfo(deviceInfo);
+                        devices.add(device);
+                    }
+                    return devices;
+                }
+            }
+        } catch (SQLException e) {
+            String msg = "Error occurred while building or executing queries to retrieve information " +
+                         "of devices with an older OS build date";
+            log.error(msg, e);
+            throw new DeviceManagementDAOException(msg, e);
+        }
+    }
+
+    @Override
+    public int getCountOfDeviceExpiredByOSVersion(String deviceType, Long osValue, int tenantId)
+            throws DeviceManagementDAOException {
+        try {
+            Connection conn = getConnection();
+            String dataSourceType = conn.getMetaData().getDatabaseProductName();
+            String sql = "SELECT " +
+                         "COUNT(ddi.DEVICE_ID) AS DEVICE_COUNT " +
+                         "FROM DM_DEVICE_INFO ddi, " +
+                         "(SELECT d.ID    AS DEVICE_ID " +
+                         "FROM DM_DEVICE_TYPE dt, " +
+                         "DM_DEVICE d " +
+                         "WHERE dt.NAME = ? " +
+                         "AND PROVIDER_TENANT_ID = ? " +
+                         "AND dt.ID = d.DEVICE_TYPE_ID " +
+                         ") d1 " +
+                         "WHERE d1.DEVICE_ID = ddi.DEVICE_ID " +
+                         "AND ddi.KEY_FIELD = ? ";
+            if (dataSourceType.contains(DeviceManagementConstants.DataBaseTypes.DB_TYPE_H2)) {
+                sql += "AND CAST( ddi.VALUE_FIELD AS BIGINT ) < ? ";
+            } else if (dataSourceType.contains(DeviceManagementConstants.DataBaseTypes.DB_TYPE_MYSQL)) {
+                sql += "AND CAST( ddi.VALUE_FIELD AS UNSIGNED ) < ? ";
+            }
+
+            try (PreparedStatement ps = conn.prepareStatement(sql)) {
+                ps.setString(1, deviceType);
+                ps.setInt(2, tenantId);
+                ps.setString(3, Constants.OS_VALUE);
+                ps.setLong(4, osValue);
+
+                try (ResultSet rs = ps.executeQuery()) {
+                    int deviceCount = 0;
+                    if (rs.next()) {
+                        deviceCount = rs.getInt("DEVICE_COUNT");
+                    }
+                    return deviceCount;
+                }
+            }
+        } catch (SQLException e) {
+            String msg = "Error occurred while building or executing queries to retrieve the count " +
+                         "of devices with an older OS build date";
+            log.error(msg, e);
+            throw new DeviceManagementDAOException(msg, e);
+        }
+    }
+
     private Connection getConnection() throws SQLException {
         return DeviceManagementDAOFactory.getConnection();
     }

components/device-mgt/org.wso2.carbon.device.mgt.core/src/main/java/org/wso2/carbon/device/mgt/core/dao/impl/device/OracleDeviceDAOImpl.java

@@ -834,52 +834,57 @@ public class OracleDeviceDAOImpl extends AbstractDeviceDAOImpl {
     public List<Device> getDevicesExpiredByOSVersion(PaginationRequest request, int tenantId)
             throws DeviceManagementDAOException {
         try {
-            Long osBuildDate = (Long) request.getProperty(Constants.OS_BUILD_DATE);
+            Long osValue = (Long) request.getProperty(Constants.OS_VALUE);
             Connection conn = getConnection();
-            String sql = "SELECT " +
+            String sql="SELECT " +
-                         "dt.NAME AS DEVICE_TYPE, " +
+                       "d1.DEVICE_TYPE, " +
-                         "d.ID AS DEVICE_ID, " +
+                       "d1.DEVICE_ID, " +
-                         "d.NAME AS DEVICE_NAME, " +
+                       "d1.DEVICE_NAME, " +
-                         "d.DESCRIPTION, " +
+                       "d1.DESCRIPTION, " +
-                         "d.DEVICE_IDENTIFICATION, " +
+                       "d1.DEVICE_IDENTIFICATION, " +
-                         "dd.OS_VERSION, " +
+                       "ddd.OS_VERSION, " +
-                         "dd.OS_BUILD_DATE, " +
                        "e.ID AS ENROLMENT_ID, " +
                        "e.OWNER, " +
                        "e.OWNERSHIP, " +
                        "e.STATUS, " +
                        "e.DATE_OF_LAST_UPDATE, " +
                        "e.DATE_OF_ENROLMENT " +
-                         "FROM DM_DEVICE d, " +
+                       "FROM DM_DEVICE_INFO ddi, " +
-                         "DM_DEVICE_DETAIL dd, " +
+                       "DM_DEVICE_DETAIL ddd, " +
                        "DM_ENROLMENT e, " +
-                         "(SELECT ID, NAME " +
+                       "(SELECT dt.NAME AS DEVICE_TYPE, " +
-                         "FROM DM_DEVICE_TYPE " +
+                       "d.ID AS DEVICE_ID, " +
-                         "WHERE NAME = ? " +
+                       "d.NAME AS DEVICE_NAME, " +
-                         "AND PROVIDER_TENANT_ID = ?) dt " +
+                       "DESCRIPTION, " +
-                         "WHERE dt.ID = d.DEVICE_TYPE_ID " +
+                       "DEVICE_IDENTIFICATION " +
-                         "AND d.ID = e.DEVICE_ID " +
+                       " FROM DM_DEVICE_TYPE dt, " +
-                         "AND d.ID = dd.DEVICE_ID " +
+                       "DM_DEVICE d " +
-                         "AND dd.OS_BUILD_DATE < ? " +
+                       "WHERE dt.NAME = ? " +
+                       "AND PROVIDER_TENANT_ID = ? " +
+                       "AND dt.ID = d.DEVICE_TYPE_ID " +
+                       ") d1 " +
+                       "WHERE d1.DEVICE_ID = e.DEVICE_ID " +
+                       "AND d1.DEVICE_ID = ddi.DEVICE_ID " +
+                       "AND ddi.KEY_FIELD = ? " +
+                       "AND CAST( ddi.VALUE_FIELD AS BIGINT ) < ? " +
                        "ORDER BY ENROLMENT_ID " +
                        "OFFSET ? ROWS " +
                        "FETCH NEXT ? ROWS ONLY";
 
             try (PreparedStatement ps = conn.prepareStatement(sql)) {
-                int paramIDx = 1;
+                ps.setString(1, request.getDeviceType());
-                ps.setString(paramIDx++, request.getDeviceType());
+                ps.setInt(2, tenantId);
-                ps.setInt(paramIDx++, tenantId);
+                ps.setString(3, Constants.OS_VALUE);
-                ps.setLong(paramIDx++, osBuildDate);
+                ps.setLong(4, osValue);
-                ps.setInt(paramIDx++, request.getStartIndex());
+                ps.setInt(5, request.getStartIndex());
-                ps.setInt(paramIDx, request.getRowCount());
+                ps.setInt(6, request.getRowCount());
 
                 try (ResultSet rs = ps.executeQuery()) {
                     List<Device> devices = new ArrayList<>();
-                    DeviceInfo deviceInfo = new DeviceInfo();
                     while (rs.next()) {
                         Device device = DeviceManagementDAOUtil.loadDevice(rs);
-                        deviceInfo.setOsVersion(rs.getString(Constants.OS_VERSION));
+                        DeviceInfo deviceInfo = new DeviceInfo();
-                        deviceInfo.setOsBuildDate(rs.getString(Constants.OS_BUILD_DATE));
+                        deviceInfo.setOsVersion(rs.getString("OS_VERSION"));
                         device.setDeviceInfo(deviceInfo);
                         devices.add(device);
                     }
@@ -887,8 +892,49 @@ public class OracleDeviceDAOImpl extends AbstractDeviceDAOImpl {
                 }
             }
         } catch (SQLException e) {
-            String msg = "Error occurred while retrieving information of devices with an older OS date " +
+            String msg = "Error occurred while building or executing queries to retrieve information " +
-                         "than the minimum date";
+                         "of devices with an older OS build date";
+            log.error(msg, e);
+            throw new DeviceManagementDAOException(msg, e);
+        }
+    }
+
+    @Override
+    public int getCountOfDeviceExpiredByOSVersion(String deviceType, Long osValue, int tenantId)
+            throws DeviceManagementDAOException {
+        try {
+            Connection conn = getConnection();
+            String sql = "SELECT " +
+                         "COUNT(ddi.DEVICE_ID) AS DEVICE_COUNT " +
+                         "FROM DM_DEVICE_INFO ddi, " +
+                         "(SELECT d.ID    AS DEVICE_ID " +
+                         "FROM DM_DEVICE_TYPE dt, " +
+                         "DM_DEVICE d " +
+                         "WHERE dt.NAME = ? " +
+                         "AND PROVIDER_TENANT_ID = ? " +
+                         "AND dt.ID = d.DEVICE_TYPE_ID " +
+                         ") d1 " +
+                         "WHERE d1.DEVICE_ID = ddi.DEVICE_ID " +
+                         "AND ddi.KEY_FIELD = ? " +
+                         "AND CAST( ddi.VALUE_FIELD AS BIGINT ) < ?";
+
+            try (PreparedStatement ps = conn.prepareStatement(sql)) {
+                ps.setString(1, deviceType);
+                ps.setInt(2, tenantId);
+                ps.setString(3, Constants.OS_VALUE);
+                ps.setLong(4, osValue);
+
+                try (ResultSet rs = ps.executeQuery()) {
+                    int deviceCount = 0;
+                    if (rs.next()) {
+                        deviceCount = rs.getInt("DEVICE_COUNT");
+                    }
+                    return deviceCount;
+                }
+            }
+        } catch (SQLException e) {
+            String msg = "Error occurred while building or executing queries to retrieve the count " +
+                         "of devices with an older OS build date";
             log.error(msg, e);
             throw new DeviceManagementDAOException(msg, e);
         }

components/device-mgt/org.wso2.carbon.device.mgt.core/src/main/java/org/wso2/carbon/device/mgt/core/dao/impl/device/PostgreSQLDeviceDAOImpl.java

@@ -24,10 +24,12 @@ import org.apache.commons.logging.LogFactory;
 import org.wso2.carbon.device.mgt.common.Count;
 import org.wso2.carbon.device.mgt.common.Device;
 import org.wso2.carbon.device.mgt.common.PaginationRequest;
+import org.wso2.carbon.device.mgt.common.device.details.DeviceInfo;
 import org.wso2.carbon.device.mgt.core.dao.DeviceManagementDAOException;
 import org.wso2.carbon.device.mgt.core.dao.DeviceManagementDAOFactory;
 import org.wso2.carbon.device.mgt.core.dao.impl.AbstractDeviceDAOImpl;
 import org.wso2.carbon.device.mgt.core.dao.util.DeviceManagementDAOUtil;
+import org.wso2.carbon.device.mgt.core.report.mgt.Constants;
 
 import java.sql.Connection;
 import java.sql.PreparedStatement;
@@ -814,6 +816,114 @@ public class PostgreSQLDeviceDAOImpl extends AbstractDeviceDAOImpl {
         }
     }
 
+    @Override
+    public List<Device> getDevicesExpiredByOSVersion(PaginationRequest request, int tenantId)
+            throws DeviceManagementDAOException {
+        try {
+            Long osValue = (Long) request.getProperty(Constants.OS_VALUE);
+            Connection conn = getConnection();
+            String sql="SELECT " +
+                       "d1.DEVICE_TYPE, " +
+                       "d1.DEVICE_ID, " +
+                       "d1.DEVICE_NAME, " +
+                       "d1.DESCRIPTION, " +
+                       "d1.DEVICE_IDENTIFICATION, " +
+                       "ddd.OS_VERSION, " +
+                       "e.ID AS ENROLMENT_ID, " +
+                       "e.OWNER, " +
+                       "e.OWNERSHIP, " +
+                       "e.STATUS, " +
+                       "e.DATE_OF_LAST_UPDATE, " +
+                       "e.DATE_OF_ENROLMENT " +
+                       "FROM DM_DEVICE_INFO ddi, " +
+                       "DM_DEVICE_DETAIL ddd, " +
+                       "DM_ENROLMENT e, " +
+                       "(SELECT dt.NAME AS DEVICE_TYPE, " +
+                       "d.ID AS DEVICE_ID, " +
+                       "d.NAME AS DEVICE_NAME, " +
+                       "DESCRIPTION, " +
+                       "DEVICE_IDENTIFICATION " +
+                       " FROM DM_DEVICE_TYPE dt, " +
+                       "DM_DEVICE d " +
+                       "WHERE dt.NAME = ? " +
+                       "AND PROVIDER_TENANT_ID = ? " +
+                       "AND dt.ID = d.DEVICE_TYPE_ID " +
+                       ") d1 " +
+                       "WHERE d1.DEVICE_ID = e.DEVICE_ID " +
+                       "AND d1.DEVICE_ID = ddi.DEVICE_ID " +
+                       "AND ddi.KEY_FIELD = ? " +
+                       "AND CAST( ddi.VALUE_FIELD AS BIGINT ) < ? " +
+                       "LIMIT ? OFFSET ?";
+
+            try (PreparedStatement ps = conn.prepareStatement(sql)) {
+                ps.setString(1, request.getDeviceType());
+                ps.setInt(2, tenantId);
+                ps.setString(3, Constants.OS_VALUE);
+                ps.setLong(4, osValue);
+                ps.setInt(5, request.getRowCount());
+                ps.setInt(6, request.getStartIndex());
+
+                try (ResultSet rs = ps.executeQuery()) {
+                    List<Device> devices = new ArrayList<>();
+                    while (rs.next()) {
+                        Device device = DeviceManagementDAOUtil.loadDevice(rs);
+                        DeviceInfo deviceInfo = new DeviceInfo();
+                        deviceInfo.setOsVersion(rs.getString("OS_VERSION"));
+                        device.setDeviceInfo(deviceInfo);
+                        devices.add(device);
+                    }
+                    return devices;
+                }
+            }
+        } catch (SQLException e) {
+            String msg = "Error occurred while building or executing queries to retrieve information " +
+                         "of devices with an older OS build date";
+            log.error(msg, e);
+            throw new DeviceManagementDAOException(msg, e);
+        }
+    }
+
+    @Override
+    public int getCountOfDeviceExpiredByOSVersion(String deviceType, Long osValue, int tenantId)
+            throws DeviceManagementDAOException {
+        try {
+            Connection conn = getConnection();
+            String sql = "SELECT " +
+                         "COUNT(ddi.DEVICE_ID) AS DEVICE_COUNT " +
+                         "FROM DM_DEVICE_INFO ddi, " +
+                         "(SELECT d.ID    AS DEVICE_ID " +
+                         "FROM DM_DEVICE_TYPE dt, " +
+                         "DM_DEVICE d " +
+                         "WHERE dt.NAME = ? " +
+                         "AND PROVIDER_TENANT_ID = ? " +
+                         "AND dt.ID = d.DEVICE_TYPE_ID " +
+                         ") d1 " +
+                         "WHERE d1.DEVICE_ID = ddi.DEVICE_ID " +
+                         "AND ddi.KEY_FIELD = ? " +
+                         "AND CAST( ddi.VALUE_FIELD AS BIGINT ) < ?";
+
+            try (PreparedStatement ps = conn.prepareStatement(sql)) {
+                ps.setString(1, deviceType);
+                ps.setInt(2, tenantId);
+                ps.setString(3, Constants.OS_VALUE);
+                ps.setLong(4, osValue);
+
+                try (ResultSet rs = ps.executeQuery()) {
+                    int deviceCount = 0;
+                    if (rs.next()) {
+                        deviceCount = rs.getInt("DEVICE_COUNT");
+                    }
+                    return deviceCount;
+                }
+            }
+        } catch (SQLException e) {
+            String msg = "Error occurred while building or executing queries to retrieve the count " +
+                         "of devices with an older OS build date";
+            log.error(msg, e);
+            throw new DeviceManagementDAOException(msg, e);
+        }
+    }
+
     private Connection getConnection() throws SQLException {
         return DeviceManagementDAOFactory.getConnection();
     }

components/device-mgt/org.wso2.carbon.device.mgt.core/src/main/java/org/wso2/carbon/device/mgt/core/dao/impl/device/SQLServerDeviceDAOImpl.java

@@ -24,12 +24,14 @@ import org.apache.commons.logging.LogFactory;
 import org.wso2.carbon.device.mgt.common.Count;
 import org.wso2.carbon.device.mgt.common.Device;
 import org.wso2.carbon.device.mgt.common.PaginationRequest;
+import org.wso2.carbon.device.mgt.common.device.details.DeviceInfo;
 import org.wso2.carbon.device.mgt.core.dao.DeviceManagementDAOException;
 import org.wso2.carbon.device.mgt.core.dao.DeviceManagementDAOFactory;
 import org.wso2.carbon.device.mgt.core.dao.impl.AbstractDeviceDAOImpl;
 import org.wso2.carbon.device.mgt.core.dao.util.DeviceManagementDAOUtil;
 import org.wso2.carbon.device.mgt.core.geo.GeoCluster;
 import org.wso2.carbon.device.mgt.core.geo.geoHash.GeoCoordinate;
+import org.wso2.carbon.device.mgt.core.report.mgt.Constants;
 
 import java.sql.Connection;
 import java.sql.PreparedStatement;
@@ -630,6 +632,114 @@ public class SQLServerDeviceDAOImpl extends AbstractDeviceDAOImpl {
         }
     }
 
+    @Override
+    public List<Device> getDevicesExpiredByOSVersion(PaginationRequest request, int tenantId)
+            throws DeviceManagementDAOException {
+        try {
+            Long osValue = (Long) request.getProperty(Constants.OS_VALUE);
+            Connection conn = getConnection();
+            String sql="SELECT " +
+                       "d1.DEVICE_TYPE, " +
+                       "d1.DEVICE_ID, " +
+                       "d1.DEVICE_NAME, " +
+                       "d1.DESCRIPTION, " +
+                       "d1.DEVICE_IDENTIFICATION, " +
+                       "ddd.OS_VERSION, " +
+                       "e.ID AS ENROLMENT_ID, " +
+                       "e.OWNER, " +
+                       "e.OWNERSHIP, " +
+                       "e.STATUS, " +
+                       "e.DATE_OF_LAST_UPDATE, " +
+                       "e.DATE_OF_ENROLMENT " +
+                       "FROM DM_DEVICE_INFO ddi, " +
+                       "DM_DEVICE_DETAIL ddd, " +
+                       "DM_ENROLMENT e, " +
+                       "(SELECT dt.NAME AS DEVICE_TYPE, " +
+                       "d.ID AS DEVICE_ID, " +
+                       "d.NAME AS DEVICE_NAME, " +
+                       "DESCRIPTION, " +
+                       "DEVICE_IDENTIFICATION " +
+                       " FROM DM_DEVICE_TYPE dt, " +
+                       "DM_DEVICE d " +
+                       "WHERE dt.NAME = ? " +
+                       "AND PROVIDER_TENANT_ID = ? " +
+                       "AND dt.ID = d.DEVICE_TYPE_ID " +
+                       ") d1 " +
+                       "WHERE d1.DEVICE_ID = e.DEVICE_ID " +
+                       "AND d1.DEVICE_ID = ddi.DEVICE_ID " +
+                       "AND ddi.KEY_FIELD = ? " +
+                       "AND CAST( ddi.VALUE_FIELD AS BIGINT ) < ? " +
+                       "LIMIT ? OFFSET ?";
+
+            try (PreparedStatement ps = conn.prepareStatement(sql)) {
+                ps.setString(1, request.getDeviceType());
+                ps.setInt(2, tenantId);
+                ps.setString(3, Constants.OS_VALUE);
+                ps.setLong(4, osValue);
+                ps.setInt(5, request.getRowCount());
+                ps.setInt(6, request.getStartIndex());
+
+                try (ResultSet rs = ps.executeQuery()) {
+                    List<Device> devices = new ArrayList<>();
+                    while (rs.next()) {
+                        Device device = DeviceManagementDAOUtil.loadDevice(rs);
+                        DeviceInfo deviceInfo = new DeviceInfo();
+                        deviceInfo.setOsVersion(rs.getString("OS_VERSION"));
+                        device.setDeviceInfo(deviceInfo);
+                        devices.add(device);
+                    }
+                    return devices;
+                }
+            }
+        } catch (SQLException e) {
+            String msg = "Error occurred while building or executing queries to retrieve information " +
+                         "of devices with an older OS build date";
+            log.error(msg, e);
+            throw new DeviceManagementDAOException(msg, e);
+        }
+    }
+
+    @Override
+    public int getCountOfDeviceExpiredByOSVersion(String deviceType, Long osValue, int tenantId)
+            throws DeviceManagementDAOException {
+        try {
+            Connection conn = getConnection();
+            String sql = "SELECT " +
+                         "COUNT(ddi.DEVICE_ID) AS DEVICE_COUNT " +
+                         "FROM DM_DEVICE_INFO ddi, " +
+                         "(SELECT d.ID    AS DEVICE_ID " +
+                         "FROM DM_DEVICE_TYPE dt, " +
+                         "DM_DEVICE d " +
+                         "WHERE dt.NAME = ? " +
+                         "AND PROVIDER_TENANT_ID = ? " +
+                         "AND dt.ID = d.DEVICE_TYPE_ID " +
+                         ") d1 " +
+                         "WHERE d1.DEVICE_ID = ddi.DEVICE_ID " +
+                         "AND ddi.KEY_FIELD = ? " +
+                         "AND CAST( ddi.VALUE_FIELD AS BIGINT ) < ?";
+
+            try (PreparedStatement ps = conn.prepareStatement(sql)) {
+                ps.setString(1, deviceType);
+                ps.setInt(2, tenantId);
+                ps.setString(3, Constants.OS_VALUE);
+                ps.setLong(4, osValue);
+
+                try (ResultSet rs = ps.executeQuery()) {
+                    int deviceCount = 0;
+                    if (rs.next()) {
+                        deviceCount = rs.getInt("DEVICE_COUNT");
+                    }
+                    return deviceCount;
+                }
+            }
+        } catch (SQLException e) {
+            String msg = "Error occurred while building or executing queries to retrieve the count " +
+                         "of devices with an older OS build date";
+            log.error(msg, e);
+            throw new DeviceManagementDAOException(msg, e);
+        }
+    }
+
     private Connection getConnection() throws SQLException {
         return DeviceManagementDAOFactory.getConnection();
     }

components/device-mgt/org.wso2.carbon.device.mgt.core/src/main/java/org/wso2/carbon/device/mgt/core/device/details/mgt/impl/DeviceInformationManagerImpl.java

@@ -18,6 +18,7 @@
 
 package org.wso2.carbon.device.mgt.core.device.details.mgt.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;
@@ -39,6 +40,7 @@ import org.wso2.carbon.device.mgt.core.device.details.mgt.DeviceInformationManag
 import org.wso2.carbon.device.mgt.core.device.details.mgt.dao.DeviceDetailsDAO;
 import org.wso2.carbon.device.mgt.core.device.details.mgt.dao.DeviceDetailsMgtDAOException;
 import org.wso2.carbon.device.mgt.core.internal.DeviceManagementDataHolder;
+import org.wso2.carbon.device.mgt.core.report.mgt.Constants;
 import org.wso2.carbon.device.mgt.core.util.DeviceManagerUtil;
 import org.wso2.carbon.device.mgt.core.util.HttpReportingUtil;
 
@@ -98,6 +100,8 @@ public class DeviceInformationManagerImpl implements DeviceInformationManager {
             } else {
                 Map<String, String> updatableProps = new HashMap<>();
                 Map<String, String> injectableProps = new HashMap<>();
+                // generate a default value depending on the devices OS version
+                addOSVersionValue(device, newDeviceInfo);
                 for (String key : newDeviceInfo.getDeviceDetailsMap().keySet()) {
                     if (previousDeviceProperties.containsKey(key)) {
                         updatableProps.put(key, newDeviceInfo.getDeviceDetailsMap().get(key));
@@ -420,5 +424,39 @@ public class DeviceInformationManagerImpl implements DeviceInformationManager {
         return newDeviceInfo;
     }
 
+    /**
+     * Generate and add a value depending on the device's OS version included in device info
+     *
+     * @param device        device data
+     * @param newDeviceInfo device info data
+     */
+    private void addOSVersionValue(Device device, DeviceInfo newDeviceInfo) {
+        String deviceTypeName = device.getType();
+        if (StringUtils.isBlank(device.getType())) {
+            if (log.isDebugEnabled()) {
+                log.debug("Unable to generate a OS version value for device type: " +
+                          deviceTypeName + ". Device type cannot be null or empty");
+            }
+        } else {
+            if (!deviceTypeName.equals("android") && !deviceTypeName.equals("ios")) {
+                if (log.isDebugEnabled()) {
+                    log.debug("Unable to generate a OS version value for device type: " +
+                              deviceTypeName + ". OS version value is only generatable for " +
+                              "android and ios");
+                }
+            } else {
+                String osVersion = newDeviceInfo.getOsVersion();
+                String osValue = String.valueOf(DeviceManagerUtil.generateOSVersionValue(osVersion));
+                if (StringUtils.isBlank(osValue)) {
+                    if (log.isDebugEnabled()) {
+                        log.debug("Unable to generate a OS version value for OS version: " +
+                                  osVersion + " for device type: " + deviceTypeName);
+                    }
+                } else {
+                    newDeviceInfo.getDeviceDetailsMap().put(Constants.OS_VALUE, osValue);
+                }
+            }
+        }
+    }
 }
 

components/device-mgt/org.wso2.carbon.device.mgt.core/src/main/java/org/wso2/carbon/device/mgt/core/report/mgt/Constants.java

@@ -1,7 +1,8 @@
 /*
- * Copyright (c) 2016, WSO2 Inc. (http://www.wso2.org) All Rights Reserved.
  *
- * WSO2 Inc. licenses this file to you under the Apache License,
+ *  Copyright (c) 2020, Entgra (pvt) Ltd. (http://entgra.io) All Rights Reserved.
+ *
+ *  Entgra (pvt) Ltd. 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
@@ -14,14 +15,21 @@
  *  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.core.report.mgt;
 
 public class Constants {
-
+    // device types
-//    device properties
+    public static final String ANDROID = "android";
+    public static final String IOS = "ios";
+    // device properties
     public static final String OS_BUILD_DATE = "OS_BUILD_DATE";
     public static final String OS_VERSION = "OS_VERSION";
+    public static final String OS_VALUE = "OS_VALUE";
+    // OS version value generating properties
+    public static final int NUM_OF_OS_VERSION_DIGITS= 5;
+    public static final int NUM_OF_OS_VERSION_POSITIONS = 3;
 }

components/device-mgt/org.wso2.carbon.device.mgt.core/src/main/java/org/wso2/carbon/device/mgt/core/report/mgt/ReportManagementServiceImpl.java

@@ -23,6 +23,9 @@ import org.apache.commons.logging.Log;
 import org.apache.commons.logging.LogFactory;
 import org.wso2.carbon.device.mgt.common.Count;
 import org.wso2.carbon.device.mgt.common.Device;
+import org.wso2.carbon.device.mgt.common.app.mgt.Application;
+import org.wso2.carbon.device.mgt.common.app.mgt.ApplicationManagementException;
+import org.wso2.carbon.device.mgt.common.exceptions.BadRequestException;
 import org.wso2.carbon.device.mgt.common.exceptions.DeviceManagementException;
 import org.wso2.carbon.device.mgt.common.PaginationRequest;
 import org.wso2.carbon.device.mgt.common.PaginationResult;
@@ -157,46 +160,55 @@ public class ReportManagementServiceImpl implements ReportManagementService {
 
     @Override
     public PaginationResult getDevicesExpiredByOSVersion(PaginationRequest request)
-            throws ReportManagementException, DeviceTypeNotFoundException {
+            throws ReportManagementException, BadRequestException {
         if (request == null ||
             StringUtils.isBlank(request.getDeviceType()) ||
-            !request.getProperties().containsKey(Constants.OS_BUILD_DATE) ||
+            request.getProperties() == null ||
-            (Long) request.getProperty(Constants.OS_BUILD_DATE) == 0) {
+            !request.getProperties().containsKey(Constants.OS_VERSION) ||
-
+            StringUtils.isBlank((String) request.getProperty(Constants.OS_VERSION))) {
             String msg = "Error Invalid data received from the request.\n" +
-                         "osBuildDate cannot be null or 0 and device type cannot be null or empty";
+                         "osVersion and device type cannot be null or empty.";
             log.error(msg);
-            throw new ReportManagementException(msg);
+            throw new BadRequestException(msg);
         }
+
+        String deviceType = request.getDeviceType();
+        if (!deviceType.equals(Constants.ANDROID) && !deviceType.equals(Constants.IOS)) {
+            String msg = "Error Invalid device type:" + deviceType + " received. Valid device types " +
+                         "are android and ios.";
+            log.error(msg);
+            throw new BadRequestException(msg);
+        }
+
         try {
             int tenantId = DeviceManagementDAOUtil.getTenantId();
-            String deviceType = request.getDeviceType();
             PaginationResult paginationResult = new PaginationResult();
-
             DeviceManagerUtil.validateDeviceListPageSize(request);
 
-            DeviceType deviceTypeObj = DeviceManagerUtil.getDeviceType(
+            String osVersion = (String) request.getProperty(Constants.OS_VERSION);
-                    deviceType, tenantId);
+            Long osVersionValue = DeviceManagerUtil.generateOSVersionValue(osVersion);
-            if (deviceTypeObj == null) {
+            if (osVersionValue == null){
-                String msg = "Error, device of type: " + deviceType + " does not exist";
+                String msg = "Failed to generate OS value, received OS version: " + osVersion +
+                             " is in incorrect format([0-9]+([.][0-9]+)*) or version is invalid.";
                 log.error(msg);
-                throw new DeviceTypeNotFoundException(msg);
+                throw new BadRequestException(msg);
             }
+            request.setProperty(Constants.OS_VALUE, osVersionValue);
 
             try {
                 DeviceManagementDAOFactory.openConnection();
-                List<Device> devices = deviceDAO.getDevicesExpiredByOSVersion(request, tenantId);
+
+                List<Device> devices = deviceDAO.getDevicesExpiredByOSVersion(
+                        request, tenantId);
                 int deviceCount = deviceDAO.getCountOfDeviceExpiredByOSVersion(
-                        deviceType,
+                        deviceType, osVersionValue, tenantId);
-                        (Long) request.getProperty(Constants.OS_BUILD_DATE),
-                        tenantId);
                 paginationResult.setData(devices);
                 paginationResult.setRecordsFiltered(devices.size());
                 paginationResult.setRecordsTotal(deviceCount);
 
                 return paginationResult;
             } catch (SQLException e) {
-                String msg = "Error occurred while opening a connection to the data source";
+                String msg = "Error occurred while opening a connection to the data source.";
                 log.error(msg, e);
                 throw new ReportManagementException(msg, e);
             } finally {
@@ -204,12 +216,12 @@ public class ReportManagementServiceImpl implements ReportManagementService {
             }
 
         } catch (DeviceManagementDAOException e) {
-            String msg = "Error occurred while retrieving expired devices by a OS build date " +
+            String msg = "Error occurred while retrieving expired devices by a OS version " +
-                         "for the tenant";
+                         "for the tenant.";
             log.error(msg, e);
             throw new ReportManagementException(msg, e);
         } catch (DeviceManagementException e) {
-            String msg = "Error occurred while validating the request";
+            String msg = "Error occurred while validating the request.";
             log.error(msg, e);
             throw new ReportManagementException(msg, e);
         }

components/device-mgt/org.wso2.carbon.device.mgt.core/src/main/java/org/wso2/carbon/device/mgt/core/util/DeviceManagerUtil.java

@@ -60,6 +60,7 @@ import org.wso2.carbon.device.mgt.core.dao.util.DeviceManagementDAOUtil;
 import org.wso2.carbon.device.mgt.core.dto.DeviceType;
 import org.wso2.carbon.device.mgt.core.internal.DeviceManagementDataHolder;
 import org.wso2.carbon.device.mgt.core.operation.mgt.util.DeviceIDHolder;
+import org.wso2.carbon.device.mgt.core.report.mgt.Constants;
 import org.wso2.carbon.identity.jwt.client.extension.JWTClient;
 import org.wso2.carbon.identity.jwt.client.extension.dto.AccessTokenInfo;
 import org.wso2.carbon.identity.jwt.client.extension.exception.JWTClientException;
@@ -89,7 +90,11 @@ import java.util.HashMap;
 import java.util.Hashtable;
 import java.util.List;
 import java.util.Map;
+import java.util.StringJoiner;
 import java.util.concurrent.TimeUnit;
+import java.util.regex.Matcher;
+import java.util.regex.Pattern;
+import java.util.stream.IntStream;
 
 
 public final class DeviceManagerUtil {
@@ -694,4 +699,86 @@ public final class DeviceManagerUtil {
         JWTClient jwtClient = jwtClientManagerService.getJWTClient();
         return jwtClient.getAccessToken(clientId, clientSecret, deviceOwner, scopes);
     }
+
+    /**
+     * <h1>Generate a value for the passed os version</h1>
+     *
+     * <p>Value is generated by isolating each position of OS version then adding Zeros up until
+     * Minor version and Revision have a constant number of digits.
+     * <i>Eg: 5.1.1 will be 50000100001, 9 will be 90000000000</i>
+     * </p>
+     *
+     * <p>Above conversion is done in order to fail proof in situations where 6.0.0 can be
+     * smaller than 5.12.1.
+     * <i>Eg: 5.12.1 will be 5121 and 6.0.0 will be 600 and 5121 > 600(this statement is incorrect)</i>
+     * </p>
+     *
+     * @param osVersion os version(eg: 5.1.1)
+     * @return {@link Long} generated value
+     */
+    public static Long generateOSVersionValue(String osVersion) {
+        Matcher osMatcher = Pattern.compile("[0-9]+([.][0-9]+)*").matcher(osVersion);
+        if (!osMatcher.find()) {
+            if (log.isDebugEnabled()) {
+                log.debug("Unable to read OS version. OS version: " + osVersion + "is invalid. " +
+                          "Please follow the following convention [0-9]+([.][0-9]+)*");
+            }
+            return null;
+        }
+        osVersion = osMatcher.group();
+
+        String[] osVersions = osVersion.split("[.]");
+        int osVersionsLength = osVersions.length;
+
+        /*
+         * <h1>Following loop will work for the value generation</h1>
+         * <p>
+         {@code Constants.NUM_OF_OS_VERSION_POSITIONS - (i + 1)} was done in-order to identify
+         which position of the OS version is been used for generation process, so correct number
+         of Zeros can be generated.
+         * </p>
+         *
+         * <p>
+         {@code Constants.NUM_OF_OS_VERSION_DIGITS} this multiplication will make sure that the
+         values generated will reduce in following order main OS version, minor OS version, Revision.
+         * </p>
+         */
+        return IntStream
+                .range(0, osVersionsLength)
+                .mapToLong(i -> (long) (Math.pow(10, (Constants.NUM_OF_OS_VERSION_POSITIONS - (i + 1))
+                                                     * Constants.NUM_OF_OS_VERSION_DIGITS)
+                                        * Integer.parseInt(osVersions[i]))).sum();
+    }
+
+    /**
+     * Revert a generated value back to a OS version
+     *
+     * @param osVersionValue value that should be reverted
+     * @return {@link String} OS version
+     */
+    /* Following method is unused but was still included in case a requirement occurs to revert the
+     * generated values in DM_DEVICE_INFO back to a OS versions */
+    public static String reverseOSVersionValue(Long osVersionValue) {
+        StringJoiner joiner = new StringJoiner(".");
+
+        /*
+        * <h1>Following loop will break the generated value into parts and will recreate the OS version</h1>
+        * <p>
+        {@code 10, (i - 1) * Constants.NUM_OF_OS_VERSION_DIGITS} this will break the generated value
+        creating each OS version position in following order main OS version, minor OS version,
+        Revision.
+        * </p>
+        *
+        */
+        for (int i = Constants.NUM_OF_OS_VERSION_POSITIONS; i > 0; i--) {
+            long osVersion = Double.valueOf(
+                    osVersionValue / Math.pow(10, (i - 1) * Constants.NUM_OF_OS_VERSION_DIGITS))
+                    .longValue();
+            osVersionValue = Double.valueOf(
+                    osVersionValue % Math.pow(10, (i - 1) * Constants.NUM_OF_OS_VERSION_DIGITS))
+                    .longValue();
+            joiner.add(String.valueOf(osVersion));
+        }
+        return joiner.toString();
+    }
 }