Returning value from Thread

by

Usually you would do it something like this

 public class Foo implements Runnable {
     private volatile int value;

     @Override
     public void run() {
        value = 2;
     }

     public int getValue() {
         return value;
     }
 }

Then you can create the thread and retrieve the value (given that the value has been set)

Foo foo = new Foo();
Thread thread = new Thread(foo);
thread.start();
thread.join();
int value = foo.getValue();

tl;dr a thread cannot return a value (at least not without a callback mechanism). You should reference a thread like an ordinary class and ask for the value.

More Related Contents:

  1. Inner class can access but not update values – AsyncTask
  2. Should I actually remove the ValueEventListener?
  3. Running code in main thread from another thread
  4. Is it legal to call the start method twice on the same Thread?
  5. How to check if current thread is not main thread
  6. java.lang.IllegalMonitorStateException: object not locked by thread before wait()?
  7. Pausing/stopping and starting/resuming Java TimerTask continuously?
  8. More efficient way for pausing loop wanted
  9. Android – Prevent white screen at startup
  10. TimerTask vs Thread.sleep vs Handler postDelayed – most accurate to call function every N milliseconds?
  11. How to wait for all tasks in an ThreadPoolExecutor to finish without shutting down the Executor?
  12. Where to stop/destroy threads in Android Service class?
  13. AsyncTask.executeOnExecutor() before API Level 11
  14. Android Timer schedule vs scheduleAtFixedRate
  15. How to use AsyncTask
  16. How to listen for Firebase setValue completion
  17. Run Handler messages in a background thread
  18. How to get the Context from anywhere? [duplicate]
  19. When may we need to use runOnUiThread in android application?
  20. How to execute web request in its own thread?
  21. What is a daemon thread in Java?
  22. Concurrent Modification Exception : adding to an ArrayList
  23. Android download binary file problems
  24. How can I make my ArrayAdapter follow the ViewHolder pattern?
  25. java Lang UnsupportedClassVersion Error in Xamarin Studio
  26. How to convert Date to a particular format in android?
  27. FileUriExposedException in Android [duplicate]
  28. Custom Layout for DialogFragment OnCreateView vs. OnCreateDialog
  29. how to resume an interrupted download
  30. Why declare a function argument to be final?

Leave a Comment