title: Waiting for a thread to finish execution
body: <p>Java newbie here. I am using a third party library which gives me a function, say F(), the output of which dictates my logic. So I need the result of it to proceed further in my code. </p>
  
  <p>The problem is F() does some I/O and so spawns off a thread to do the functionality. They gave me a few callbacks to implement which are called to return the status/values from the thread. This is fine except that the function F() returns immediately and the rest of my code keeps running. I don't want that as I have to allocate some objects based on the outcome of F() and so I really want to wait for F() to really finish. </p>
  
  <p>This should be a problem people run into quite often. What is the correct way to deal with this? Is it a problem in my design or the third party library? Or did I not understand the library very well?</p>
  
  <p>For the sake of completeness I am working on an android app and the library is the facebook sdk. The function is the single sign-on function authorize(). Though this is a generic enough problem that I thought is best addressed in the Java forum.</p>
  
  <p>Thanks for any help.
  - P</p>