friendhandler.java

该系统是一个基于p2p的即时聊天系统

/*
 * @(#) FriendHandler.java
 * Copyright 2004 HWStudio. All rights reserved.
 */
package hws.item.smart.utility.admin;
//导入核心Java类库
import java.io.IOException;
import java.io.StringReader;
import java.util.List;
//导入第三方Java类库
import org.jdom.Element;
import org.jdom.Document;
import org.jdom.JDOMException;
import org.jdom.input.SAXBuilder;
import org.jdom.output.XMLOutputter;
/**
 * 好友处理器
 *
 * @version 0.1 2005-08-06
 * @author Hwerz
 */
public class FriendHandler extends Object {
    /*------------------------------------------------------------------------*
     *                                公共方法                                *
     *------------------------------------------------------------------------*/
    /**
     * 好友信息
     *
     * @param requestMsg 好友信息的请求信息
     * @return 好友信息的响应信息
     */
    public String friend(String requestMsg) {
        Element response = new Element("Response");
        try {
            SAXBuilder builder = new SAXBuilder();
            StringReader reader = new StringReader(requestMsg);
            Document document = builder.build(reader);
            Element request = document.getRootElement();
            String id = request.getChild("ID").getText();
            List ids = XMLAccessor.getAllUsersID();
            for (int i = 0; i < ids.size(); i++) {
                String id2 = ids.get(i).toString();
                if (id2.equals(id) == false && isMyFriend(id2, id) == false) {
                    response.addContent(XMLAccessor.getUserElement(id2, true));
                }
            }
        } catch (JDOMException e) {
            e.printStackTrace();
        } catch (IOException e) {
            e.printStackTrace();
        }
        XMLOutputter outputter = new XMLOutputter();
        return outputter.outputString(new Document(response));
    }
    /*------------------------------------------------------------------------*
     *                                私有方法                                *
     *------------------------------------------------------------------------*/
    /**
     * 判断第一个用户是否是第二个用户的好友，如果是则返回true，否则返回false
     *
     * @param id1 第一个用户
     * @param id2 第二个用户
     * @return 如果第一个用户是第二个用户的好友则返回true，否则返回false
     */
    private boolean isMyFriend(String id1, String id2) {
        boolean is = false;
        List friends = XMLAccessor.getAllFriends(id2);
        for (int i = 0; i < friends.size(); i++) {
            if (friends.get(i).equals(id1) == true) {
                is = true;
                break;
            }
        }
        return is;
    }
}