JSP线上水球游戏开发环境Tomcat 5.5.x + JDK 5.0（不要在JDK 1.4.x的JVM上跑）

				package com.andowson.onlineuser;

				

				import java.io.Serializable;

				import java.util.Map;

				import java.util.Set;

				import java.util.concurrent.ConcurrentMap;

				import java.util.concurrent.ConcurrentHashMap;

				

				/**

				 * UserList

				 *    a singleton class

				 *

				 * @version 0.0.1 2004/12/22

				 * @author Andowson Chang

				 */

				public class UserList implements Serializable {

				

				    private ConcurrentMap container = new ConcurrentHashMap();

				  

				    // UserList 衡琌