/* (non-Javadoc)
  * @see org.eclipse.tcf.te.core.async.AsyncCallbackHandler#removeCallback(org.eclipse.tcf.te.runtime.interfaces.callback.ICallback)
  */
 @Override
 public final synchronized void removeCallback(ICallback callback) {
   super.removeCallback(callback);
   checkAndFireCallback();
 }
 /* (non-Javadoc)
  * @see org.eclipse.tcf.te.core.async.AsyncCallbackHandler#addCallback(org.eclipse.tcf.te.runtime.interfaces.callback.ICallback)
  */
 @Override
 public final synchronized void addCallback(ICallback callback) {
   Assert.isTrue(!isFinished() || getError() != null);
   super.addCallback(callback);
 }