Adding null check for operations response

components/mobile-plugins/android-plugin/org.wso2.carbon.device.mgt.mobile.android.api/src/main/java/org/wso2/carbon/mdm/services/android/util/AndroidAPIUtils.java

@@ -312,6 +312,7 @@ public class AndroidAPIUtils {
     private static void updateApplicationList(Operation operation, DeviceIdentifier deviceIdentifier)
             throws ApplicationManagementException {
         // Parsing json string to get applications list.
+        if (operation.getOperationResponse() != null) {
             JsonElement jsonElement = new JsonParser().parse(operation.getOperationResponse());
             JsonArray jsonArray = jsonElement.getAsJsonArray();
             Application app;
@@ -332,6 +333,10 @@ public class AndroidAPIUtils {
                 applications.add(app);
             }
             getApplicationManagerService().updateApplicationListInstalledInDevice(deviceIdentifier, applications);
+        } else {
+            log.error("Operation Response is null.");
+        }
+
     }