fix(license): Improve exception handling

Improve exception handling in uploadLicense method #3895

Co-authored-by: Gaurav Mishra <gmishx@gmail.com>
Signed-off-by: keerthi-bl <121924406+keerthi-bl@users.noreply.github.com>

Author: Bhawanishanker22

rest/resource-server/src/main/java/org/eclipse/sw360/rest/resourceserver/license/Sw360LicenseService.java

@@ -269,17 +269,28 @@ private void copyDataStreamToResponse(HttpServletResponse response, ByteArrayInp
         FileCopyUtils.copy(buffer, response.getOutputStream());
     }
 
-    public void uploadLicense(User sw360User, MultipartFile file, boolean overwriteIfExternalIdMatches, boolean overwriteIfIdMatchesEvenWithoutExternalIdMatch) throws IOException, TException {
-        final HashMap<String, InputStream> inputMap = new HashMap<>();
+    public void uploadLicense(User sw360User, MultipartFile file, boolean overwriteIfExternalIdMatches, boolean overwriteIfIdMatchesEvenWithoutExternalIdMatch)
+            throws IOException, TException {
+
+        if (file == null || file.isEmpty()) {
+            throw new BadRequestClientException("Unable to upload license file. File is null or empty.");
+        }
 
         if (!PermissionUtils.isUserAtLeast(UserGroup.ADMIN, sw360User)) {
-            throw new BadRequestClientException("Unable to upload license file. User is not admin");
+            throw new BadRequestClientException("Unable to upload license file. User is not admin.");
         }
+
+        final HashMap<String, InputStream> inputMap = new HashMap<>();
+        Throwable primaryThrowable = null;
+
         try (InputStream inputStream = file.getInputStream()) {
             ZipTools.extractZipToInputStreamMap(inputStream, inputMap);
             LicenseService.Iface sw360LicenseClient = getThriftLicenseClient();
             final LicsImporter licsImporter = new LicsImporter(sw360LicenseClient, overwriteIfExternalIdMatches, overwriteIfIdMatchesEvenWithoutExternalIdMatch);
             licsImporter.importLics(sw360User, inputMap);
+        } catch (Throwable t) {
+            primaryThrowable = t;
+            throw t;
         } finally {
             IOException closeFailure = null;
             for (InputStream in : inputMap.values()) {
@@ -293,11 +304,16 @@ public void uploadLicense(User sw360User, MultipartFile file, boolean overwriteI
                     }
                 }
             }
+
             if (closeFailure != null) {
-                throw closeFailure;
+                if (primaryThrowable != null) {
+                    primaryThrowable.addSuppressed(closeFailure);
+                } else {
+                    throw closeFailure;
+                }
             }
         }
-	}
+    }
 
     public RequestSummary importOsadlInformation(User sw360User) throws TException {
         LicenseService.Iface sw360LicenseClient = getThriftLicenseClient();