title: java.util.ConcurrentModificationException in For loop
body: <p>I am trying to program an IM software,
  I want to let user leave the conversation and tell his partner that he has left...
  I prefer to use for loop instead Iterator, seek all the users and get the user who ask to leave and remove him... like that:</p>
  
  <pre><code>   for(Clientuser Cu: EIQserver.OnlineusersList)
            if(Cu.ID.equals(thsisUser.ID)) // find the user who ask to leave 
            {
            Omsg.setBody("@@!&amp;$$$$@@@####$$$$"); //code means : clien! ur parter leaves...
                   sendMessage(Omsg); // sed message to thje partner with that code
                   EIQserver.OnlineusersList.remove(Cu);// remove the partner
                  EIQserver.COUNTER--;// decrease counter.
  
            }
  </code></pre>
  
  <p>I get Exception: java.util.ConcurrentModificationException</p>
  
  <p>I was using iterators, and to get rid of this exception, I convert to for, but the same exception still appears!!
  how may I get rid of this exception?</p>