Null pointer exception running connected test in Android studio

Question

I am trying to execute connected test for P4, however I am reciing an "Null pointer exception error" for P4

Error message:

:00:02 PM null
java.lang.NullPointerException
at com.android.ddmlib.Client.read(Client.java:692)
at com.android.ddmlib.MonitorThread.processClientActivity(MonitorThread.java:304)
at com.android.ddmlib.MonitorThread.run(MonitorThread.java:256)

It is a standard test, verifying non-empty string in the Async task

Test function:

public void runCloudModuleTest() {
    String joke = null;
    JokesAsyncTask jokesAsyncTask = new JokesAsyncTask(getContext(), null);
    jokesAsyncTask.execute();
    try {
        joke = jokesAsyncTask.get();
        Log.d("CloudModuleTest", "Retrieved a non-empty string successfully: " + joke);
    } catch (Exception e) {
        e.printStackTrace();
    }
    assertNotNull(joke);
}

Can someone help me understand what the issue is?

AsyncTask: The Async task pulls data from google cloud engine

public class JokesAsyncTask extends AsyncTask, Void, String> {

private static JokeApi myApiService = null;
private Context mContext;
private String mResult;
private ProgressBar mProgressBar;

public JokesAsyncTask(Context context, ProgressBar progressBar) {
    this.mContext = context;
    this.mProgressBar = progressBar;
}

@Override
protected void onPreExecute() {
    super.onPreExecute();
    if (mProgressBar != null) {
        mProgressBar.setVisibility(View.VISIBLE);
    }
}

@Override
protected String doInBackground(Pair<Context, String>... pairs) {
    if (myApiService == null) {
        JokeApi.Builder builder = new JokeApi.Builder(AndroidHttp.newCompatibleTransport(),
                new AndroidJsonFactory(), null)
                .setRootUrl("https://testandroiddevelopment.appspot.com/_ah/api/");
        myApiService = builder.build();
    }
    try {
        return myApiService.sendJoke(new JokeBean()).execute().getJoke();
    } catch (IOException e) {
        return e.getMessage();
    }
}

@Override
protected void onPostExecute(String result) {
    super.onPostExecute(result);

    if (mProgressBar != null) {
        mProgressBar.setVisibility(View.GONE);
    }
    mResult = result;
    startJokeDisplayActivity();
}

private void startJokeDisplayActivity() {

    Intent intent = new Intent(mContext, JokeViewActivity.class);
    intent.putExtra(JokeViewActivity.JOKE_KEY, mResult);
    intent.addFlags(Intent.FLAG_ACTIVITY_NEW_TASK);
    mContext.startActivity(intent);
}

}

I have referenced the variable and it is not an issue due due to the below post, however I did investigate and finally cleaned up and rebuild the project that helped resolved the issue

What is printing null before the exception? It seems your AsyncTask is returning null, so show your JokesAsyncTask class — OneCricketeer
myApiService is OkHttp or Retrofit? Why do you need an AsyncTask for that? — OneCricketeer
I am doing one of the project with Udacity Android and the requirement is to create an Async task to retrieve data from GCE. MyAPI service is not okhttp or retrofit — Mahesh N
Well, I haven't used GCE, but I do know that you more than likely should be using the Async features of AsyncTask. By using the get() method on it, you've forced it back to synchronous code. Unfortunately, unit-testing asynchronous code doesn't make much sense. — OneCricketeer

Mahesh N Mahesh N · Accepted Answer · 2016-11-09T16:13:57

I have referenced the variable and it is not an issue due due to the post @AxelH, however I did investigate and finally cleaned up and rebuild the project that helped resolved the issue

Null pointer exception running connected test in Android studio

1 Answers