com.threerings.util
Class ChangeBlock

java.lang.Object
  com.threerings.util.ChangeBlock

public class ChangeBlock
extends Object

A simple mechanism for preventing infinite recursion when one change listener responds to an event by making another change, which in turns notifies another (or the same) listener, which makes another change, and so on. The following example demonstrates the pattern:

 public void stateChanged (ChangeEvent event)
 {
     if (!_block.enter()) {
         return;
     }
     try {
         // do something that may cause another state change
     } finally {
         _block.leave();
     }
 }
 

Field Summary

protected boolean

_changing If true, the current thread is in the change block.

Constructor Summary

ChangeBlock()

Method Summary

boolean	enter() Attempts to enter the change block.
void	leave() Leaves the change block.

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Field Detail

_changing

protected boolean _changing

If true, the current thread is in the change block.

Constructor Detail

ChangeBlock

public ChangeBlock()

Method Detail

enter

public boolean enter()

Attempts to enter the change block.

Returns:

true if the change block was successfully entered, false if already in the change block.

leave

public void leave()

Leaves the change block.