public boolean enqueue(Object obj) {
        return enqueue(obj, Integer.MAX_VALUE);
    }
Enqueue an object on this queue. If the queue has been closed,
the object will not be queued, and this method will return
false.

@return true if the object was enqueued, false if this queue
was closed
@param obj the object to enqueue
jrt/src/com/yahoo/jrt/ThreadQueue.java