Question

I have a project that does 2 RPC calls and then saves the data that the user provided in tha datastore. The first RPC call works ok, but from the second I always recieve the onFailure() message. How can I determine why the onFailure() is triggered? I tried caught.getCause() but it doesn’t return anything.

feedbackService.saveFeedback(email,studentName,usedTemplates,
    new AsyncCallback<String>() {

    public void onFailure(Throwable caught) {
        // Show the RPC error message to the user
        caught.getCause();
        Window.alert("Failure!");
    }

    public void onSuccess(String result) {
        Window.alert("Saved!");
    }
});

Answer 1

Throwable instance is instance of an Exception. You can check if it is a custom Exception like this:

if (caught instanceOf CustomException){

or if you want to show the message of exception you can use the getMessage():

Window.alert("Failure: " + caught.getMessage());