replyfactory.java

基于struct结构的jsp

package com.ntsky.bbs.service;

import java.util.*;

import org.apache.log4j.Logger ;

/**
 * <p>Title: Ntsky OpenSource BBS</p>
 * <p>Description: 回复信息实现类</p>
 * <p>Copyright: Copyright (c) 2004</p>
 * <p>Company: 天网文化发展有限公司</p>
 * @author 姚君林
 * @version 1.0
 */

public abstract class ReplyFactory {
    private final static Logger logger = Logger.getLogger(TopicFactory.class);
    private static Object initLock = new Object();
    private static ReplyFactory factory = null;
    private final static String CLASSNAME =
        "com.ntsky.bbs.service.db.DBReplyFactory";

    public abstract void insReply(Reply reply);

    public abstract void upReply(Reply reply);

    public abstract Reply listReplySin(int repId);

    public abstract void delTopicReply(int topicId);

    public abstract void delReply(int repId);
    /**
     * 回复信息
     * @param topicId int
     * @return Iterator
     */
    protected abstract Iterator listReply(int topicId);

    /**
     * 获取UserFactory实例,使用了简单工厂模式
     * @return
     */
    public static ReplyFactory getInstance() {
        if (factory == null) {
            //使用synchronzed保证一次只有一个实例能访问DBUser对象
            synchronized (initLock) {
                if (factory == null) {
                    try {
                        //创建DBUser的一个实例
                        Class c = Class.forName(CLASSNAME);
                        factory = (ReplyFactory) c.newInstance();
                        logger.info("获取帖子处理的实例成功");
                    }
                    catch (Exception e) {
                        System.err.println(
                            "ReplyFactory Exception loading class: " +
                            e.getMessage());
                        e.printStackTrace();
                    }
                }
            }
        }
        return factory;
    }

}