title: child thread to parent thread communication
body: <p>I am working on a java multi-threaded application on Android.</p>
  
  <p>Thread 1: Listener Thread.
  keep listening on a socket, fires 2nd thread for some action</p>
  
  <p>Thread 2: Action Thread.
  short lived. get fired from first thread, do a simple action and dies.</p>
  
  <p>Thread 1 does not wait on Thread 2, as it goes back to listening after firing Thread 2.</p>
  
  <p>Can I execute a method in Thread1 (say thread2ActionCompleted()) from Thread2 just before it ends.</p>
  
  <p>For some reason I cannot use static method or static variable in Thread 1</p>
  
  <p>I saw some similar threads using <code>ExecutorService</code>, but couldn't find a good example if it will work in my situation.</p>