Add requested changes

components/application-mgt/io.entgra.device.mgt.core.application.mgt.core/src/main/java/io/entgra/device/mgt/core/application/mgt/core/impl/ApplicationManagerImpl.java

@@ -732,7 +732,8 @@ public class ApplicationManagerImpl implements ApplicationManager {
         int tenantId = PrivilegedCarbonContext.getThreadLocalCarbonContext().getTenantId(true);
         ApplicationStorageManager applicationStorageManager = APIUtil.getApplicationStorageManager();
         try {
-            String md5OfApp = applicationStorageManager.getMD5(Files.newInputStream(Paths.get(applicationArtifact.getInstallerPath())));
+            String md5OfApp = applicationStorageManager.
+                    getMD5(Files.newInputStream(Paths.get(applicationArtifact.getInstallerPath())));
             validateReleaseBinaryFileHash(md5OfApp);
             releaseDTO.setUuid(UUID.randomUUID().toString());
             releaseDTO.setAppHashValue(md5OfApp);
@@ -748,6 +749,7 @@ public class ApplicationManagerImpl implements ApplicationManager {
             String msg = "Error occurred while md5sum value retrieving process: application UUID "
                     + releaseDTO.getUuid();
             log.error(msg, e);
+            throw new ApplicationManagementException(msg, e);
         }
         return addImageArtifacts(releaseDTO, applicationArtifact, tenantId);
     }
@@ -896,7 +898,8 @@ public class ApplicationManagerImpl implements ApplicationManager {
                     log.error(msg);
                     throw new ApplicationManagementException(msg);
                 }
-                String md5OfApp = applicationStorageManager.getMD5(Files.newInputStream(Paths.get(applicationArtifact.getInstallerPath())));
+                String md5OfApp = applicationStorageManager.
+                        getMD5(Files.newInputStream(Paths.get(applicationArtifact.getInstallerPath())));
                 if (md5OfApp == null) {
                     String msg = "Error occurred while md5sum value retrieving process: application UUID "
                             + applicationReleaseDTO.getUuid();
@@ -910,7 +913,6 @@ public class ApplicationManagerImpl implements ApplicationManager {
                     throw new BadRequestException(msg);
                 }
                 applicationReleaseDTO.setAppHashValue(md5OfApp);
-
                 applicationStorageManager
                         .uploadReleaseArtifact(applicationReleaseDTO, deviceType,
                                 Files.newInputStream(Paths.get(applicationArtifact.getInstallerPath())), tenantId);

components/application-mgt/io.entgra.device.mgt.core.application.mgt.core/src/main/java/io/entgra/device/mgt/core/application/mgt/core/impl/ApplicationStorageManagerImpl.java

@@ -156,7 +156,6 @@ public class ApplicationStorageManagerImpl implements ApplicationStorageManager
     public void uploadReleaseArtifact(ApplicationReleaseDTO applicationReleaseDTO,
             String deviceType, InputStream binaryFile, int tenantId) throws ResourceManagementException {
         try {
-            //byte [] content = IOUtils.toByteArray(binaryFile);
             String artifactDirectoryPath =
                     storagePath + tenantId + File.separator + applicationReleaseDTO.getAppHashValue() + File.separator
                             + Constants.APP_ARTIFACT;

components/application-mgt/io.entgra.device.mgt.core.application.mgt.core/src/main/java/io/entgra/device/mgt/core/application/mgt/core/impl/FileTransferServiceImpl.java

@@ -31,6 +31,7 @@ import io.entgra.device.mgt.core.device.mgt.common.exceptions.NotFoundException;
 import org.apache.commons.logging.Log;
 import org.apache.commons.logging.LogFactory;
 
+import java.io.IOException;
 import java.io.InputStream;
 import java.net.URL;
 import java.nio.file.FileSystems;
@@ -103,8 +104,13 @@ public class FileTransferServiceImpl implements FileTransferService {
     @Override
     public boolean isExistsOnLocal(URL downloadUrl) throws FileTransferServiceException {
         try {
-            return FileTransferServiceHelperUtil.resolve(downloadUrl) != null;
-        } catch (FileTransferServiceHelperUtilException e) {
+            FileDescriptor fileDescriptor = FileTransferServiceHelperUtil.resolve(downloadUrl);
+            if (fileDescriptor != null && fileDescriptor.getFile() != null) {
+                fileDescriptor.getFile().close();
+                return true;
+            }
+            return false;
+        } catch (FileTransferServiceHelperUtilException | IOException e) {
             String msg = "Error occurred while checking the existence of artifact on the local environment";
             log.error(msg, e);
             throw new FileTransferServiceException(msg, e);

components/application-mgt/io.entgra.device.mgt.core.application.mgt.core/src/main/java/io/entgra/device/mgt/core/application/mgt/core/util/FileTransferServiceHelperUtil.java

@@ -244,9 +244,10 @@ public class FileTransferServiceHelperUtil {
     }
 
     private static FileDescriptor resolve(String []urlSegments) throws FileTransferServiceHelperUtilException {
+        // check the possibility of url is pointing to a file resides in  the default storage path
         if (urlSegments.length < 4) {
             if (log.isDebugEnabled()) {
-                log.debug("URL path segments contain less than 2 segments");
+                log.debug("URL path segments contain less than 4 segments");
             }
             return null;
         }