refactoring

modules/samples/virtual_firealarm/src/org.wso2.carbon.device.mgt.iot.sample.virtual.firealarm.service.impl/src/main/java/org/wso2/carbon/device/mgt/iot/sample/virtual/firealarm/service/impl/VirtualFireAlarmService.java

@@ -297,7 +297,7 @@ public class VirtualFireAlarmService {
 				}
 			}
 
-			return userDevicesforFirealarm.toArray(new Device[]{});
+			return userDevicesforFirealarm.toArray(new Device[] {});
 		} catch (DeviceManagementException e) {
 			response.setStatus(Response.Status.INTERNAL_SERVER_ERROR.getStatusCode());
 			return null;
@@ -641,6 +641,8 @@ public class VirtualFireAlarmService {
 			sensorRecord = SensorDataManager.getInstance().getSensorRecord(deviceId, VirtualFireAlarmConstants.SENSOR_TEMPERATURE);
 		} catch (DeviceManagementException e) {
 			response.setStatus(Response.Status.INTERNAL_SERVER_ERROR.getStatusCode());
+        } catch (DeviceControllerException e){
+			response.setStatus(Response.Status.INTERNAL_SERVER_ERROR.getStatusCode());
 		}
 
 		response.setStatus(Response.Status.OK.getStatusCode());