Does long running thread result in Activity memory leaks?

Question

I've written a Utilloader class which provide a loader thread that load some data from net. in my activity I start a new loader thread. The thread then update the activity via handler.post().

class MyActivity extends Activity
{
  public void onCreate(Bundle savedInstanceState)
  {
    super.onCreate(savedInstanceState);
    initUI();
    UtilLoader.getInstance().load("url", new UtilLoad.OnLoadListener
    {
      public void onLoadSuccess(String response)
      {
         updateUI();
      }
    });
  }
}

class UtilLoader
{
  private Handler handler = new Handler();
  private UtilLoader instance = new UtilLoader();
  private ExecutorService executorService = Executors.newFixedThreadPool(3);
  public interface OnLoadListener
  {
    public void onLoadSuccess(String response);
  }
  public UtilLoader getInstance()
  {
    return instance;
  }
  public load(String url, OnLoadListener onLoadListener)
  {
    executorService.submit(new Loader(url, onLoadListener));
  }
  public class Loader extends Runnable
  {
     private String url;
     private OnLoadListener onLoadListener;
     public Loader(String url, OnLoadListener onLoadListener)
     {
        this.url = url;
        this.onLoadListener = onLoadListener;
     }
     public void run()
     {
        // LOAD DATA
        handler.post(new Runnable() {        
           public void run() {
             onLoadListener.onLoadSuccess(sb.toString());
           }
        });
     }
  }
}

Does this way of activity updating result in memory leaks by keeping a reference to the activity? If yes how must I change it, so there is no memory leaks?

yes, if you are setting a callback i.e. updateUI() it will definitely result in memory leak by keep a reference to it thus preventing the GC from collecting it. — Jitender Dev, Nov 07 '13 at 09:06

score 0 · Answer 1 · answered Nov 07 '13 at 09:06

0

Yes, the UtilLoader holds a reference to the anonymous inner class which you pass in as OnLoadListener and this anonymous inner class in turn holds a reference to the activity.

answered Nov 07 '13 at 09:06

Henry

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You can for example use a service and bind and unbind your activity dynamically – Henry Nov 07 '13 at 09:09
a service only for loading some internal data? can I use Handler message instead? – Ali Nov 07 '13 at 09:11
@Ali check this if it helps http://www.androiddesignpatterns.com/2013/01/inner-class-handler-memory-leak.html – Raghunandan Nov 07 '13 at 09:16
Another possibility is to use Android loaders: http://developer.android.com/guide/components/loaders.html – Henry Nov 07 '13 at 09:16
@Raghunandan Can I use weak reference to the activity in my code? – Ali Nov 07 '13 at 09:21
@Ali if your using the activity context in an inner class yes use a weak reference and make the inner class static – Raghunandan Nov 07 '13 at 09:35

score 0 · Answer 2 · answered Nov 07 '13 at 09:07

0

yes, if you are setting a callback i.e. updateUI() it will definitely result in memory leak by keep a reference to it thus preventing the GC from collecting it.

answered Nov 07 '13 at 09:07

Jitender Dev

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score 0 · Answer 3 · edited May 23 '17 at 12:21

0

It's possible. As long as the Looper associated with the handler has messages in the queue, it will keep a reference to the associated Activity/Service. This could be a problem for long-running operations. See this thread for more:

This Handler class should be static or leaks might occur: IncomingHandler

edited May 23 '17 at 12:21

Community

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answered Nov 07 '13 at 09:08

Anup Cowkur

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Does long running thread result in Activity memory leaks?

3 Answers3