jade代码札记 receive(pattern)

jade代码笔记 receive(pattern)
receive(MessageTemplate pattern)是一个线程安全的方法，对msgQueue做同步，即一次只有一个receive访问msgQueue，遍历队列，直到找到与pattern匹配的消息，先保存当前消息，再从队列中删除，并告知agenttoolkit已得到消息(MIDP与手机有关)，再返回这个消息。
public final ACLMessage receive(MessageTemplate pattern) {
ACLMessage msg = null;
synchronized (msgQueue) {
for (Iterator messages = msgQueue.iterator(); messages.hasNext(); ) {
final ACLMessage cursor = (ACLMessage)messages.next();
if (pattern == null || pattern.match(cursor)) {
try {
//messages.remove();
msgQueue.remove(cursor);
//#MIDP_EXCLUDE_BEGIN
notifyReceived(cursor);
//#MIDP_EXCLUDE_END
currentMessage = cursor;
msg = cursor;
break; // Exit while loop
}
catch (Exception e) {
e.printStackTrace();
// Continue loop, discard message
}
}
}
}
return msg;
}