Stackdriver Error Reporting on Play Framework 1.4

Application.java

public class Application extends Controller {

    @Catch(value={Exception.class})
    public static void onException(Exception ex) {
        StringWriter exceptionWriter = new StringWriter();
        ex.printStackTrace(new PrintWriter(exceptionWriter));
        
        Map<String, Object> payload = new HashMap<String, Object>();
        payload.put("message", exceptionWriter.toString());
        Map<String,String> serviceContextData = new HashMap<String, String>();
        serviceContextData.put("service", "randomgift");
        payload.put("serviceContext", serviceContextData);
        Gson gson = new Gson();
        String payloadStr = gson.toJson(payload); 
        
        Map<String, String> headers = new HashMap<String,String>();
        headers.put("Content-Type", "application/json");
        
        // Report to Stackdriver Error Reporting:
        String apikey = "<your-api-key>";
        String projectName = "<your-project-id>";
        WS.url("https://clouderrorreporting.googleapis.com/v1beta1/projects/" + projectName + "/events:report?key=" + apikey)
          .headers(headers)
          .body(payloadStr)
          .post();
          
        Logger.info("Error reported");
    }
    
 }