java在线聊天项目1.3版设计好友列表框功能补充，因只要用户登录就发送一串新列表，导致不同客户端好友列表不同问题

解决完毕后效果图：

好友列表Vector添加的时候进行判断，如果有相同的则不添加

int flag=0;
for (int i = 0; i < names.size(); i++) {
if (name.equals(names.get(i))) {
flag=1;
}
}
if(flag==0) {
names.add(name);
}

好友列表窗代码如下：

package com.swift.frame;

import java.awt.BorderLayout;
import java.awt.Component;
import java.awt.Container;
import java.awt.Dimension;
import java.awt.FlowLayout;
import java.awt.event.MouseAdapter;
import java.awt.event.MouseEvent;
import java.awt.event.WindowAdapter;
import java.awt.event.WindowEvent;
import java.io.DataInputStream;
import java.io.DataOutputStream;
import java.io.IOException;
import java.net.Socket;
import java.net.SocketException;
import java.util.ArrayList;
import java.util.List;
import java.util.Vector;

import javax.swing.DefaultListModel;
import javax.swing.ImageIcon;
import javax.swing.JButton;
import javax.swing.JDialog;
import javax.swing.JFrame;
import javax.swing.JLabel;
import javax.swing.JList;
import javax.swing.JMenu;
import javax.swing.JMenuBar;
import javax.swing.JMenuItem;
import javax.swing.JPanel;
import javax.swing.JPopupMenu;
import javax.swing.JTabbedPane;
import javax.swing.SwingConstants;
import javax.swing.UIManager;
import javax.swing.UnsupportedLookAndFeelException;

public class FriendsFrame extends JFrame {

    private static final long serialVersionUID = 1L;
    private Socket s;
    private DataOutputStream dos;
    private DataInputStream dis;
    private boolean connected = false;
    Vector<String> names = new Vector<String>();
    JList<String> list = null;

    public FriendsFrame(String name, Socket socket) {
        super("欢迎 " + ":" + socket.getLocalPort());
        this.s = socket;
        connected = true;
        names.add("登录用户");
        try {
            this.dos = new DataOutputStream(s.getOutputStream());
            this.dis = new DataInputStream(s.getInputStream());
        } catch (IOException e) {
            e.printStackTrace();
        }
        JFrame.setDefaultLookAndFeelDecorated(true);
        JDialog.setDefaultLookAndFeelDecorated(true);

        try {
            UIManager.setLookAndFeel("javax.swing.plaf.nimbus.NimbusLookAndFeel");
        } catch (ClassNotFoundException e1) {
            e1.printStackTrace();
        } catch (InstantiationException e1) {
            e1.printStackTrace();
        } catch (IllegalAccessException e1) {
            e1.printStackTrace();
        } catch (UnsupportedLookAndFeelException e1) {
            e1.printStackTrace();
        }

        setBounds(100, 100, 247, 581);
        setVisible(true);
        final JPanel panel = new JPanel();
        panel.setLayout(new BorderLayout());
        getContentPane().add(panel, BorderLayout.NORTH);

        final JLabel label = new JLabel(new ImageIcon("Images/logo.jpg"));
        label.setText("New JLabel");
        panel.add(label, BorderLayout.WEST);
        label.setPreferredSize(new Dimension(74, 74));

        final JPanel panel_1 = new JPanel();
        panel_1.setLayout(new BorderLayout());
        panel.add(panel_1, BorderLayout.CENTER);

        final JLabel advancingSwiftLabel = new JLabel();
        advancingSwiftLabel.setText(name);
        panel_1.add(advancingSwiftLabel, BorderLayout.CENTER);

        final JLabel neverWasterLabel = new JLabel();
        neverWasterLabel.setText("Never waste time any more");
        panel_1.add(neverWasterLabel, BorderLayout.SOUTH);

        final JPanel panel_2 = new JPanel();
        panel_2.setLayout(new BorderLayout());
        getContentPane().add(panel_2, BorderLayout.SOUTH);

        final JPanel panel_3 = new JPanel();
        final FlowLayout flowLayout = new FlowLayout();
        flowLayout.setAlignment(FlowLayout.LEFT);
        panel_3.setLayout(flowLayout);
        panel_2.add(panel_3);

        final JButton button = new JButton();
        panel_3.add(button);
        button.setHorizontalTextPosition(SwingConstants.LEFT);
        button.setHorizontalAlignment(SwingConstants.LEFT);
        button.setText("设置");

        final JButton button_1 = new JButton();
        panel_3.add(button_1);
        button_1.setText("查找");

        final JPanel panel_4 = new JPanel();
        panel_2.add(panel_4, BorderLayout.EAST);

        final JButton button_2 = new JButton();
        panel_4.add(button_2);
        button_2.setText("退出");

        final JTabbedPane tabbedPane = new JTabbedPane();
        getContentPane().add(tabbedPane, BorderLayout.CENTER);

        final JPanel panel_5 = new JPanel();
        tabbedPane.addTab("好友列表", null, panel_5, null);
        list = new JList<String>();

        panel_5.add(list);

        final JPanel panel_6 = new JPanel();
        tabbedPane.addTab("群聊", null, panel_6, null);

        final JPanel panel_7 = new JPanel();
        tabbedPane.addTab("聊天记录", null, panel_7, null);

        this.setDefaultCloseOperation(EXIT_ON_CLOSE);

        final JMenuBar menuBar = new JMenuBar();
        setJMenuBar(menuBar);

        final JMenu menu = new JMenu();
        menu.setText("操作");
        menuBar.add(menu);

        final JMenuItem newItemMenuItem = new JMenuItem();
        newItemMenuItem.setText("设置");
        menu.add(newItemMenuItem);

        final JMenuItem newItemMenuItem_1 = new JMenuItem();
        newItemMenuItem_1.setText("空间");
        menu.add(newItemMenuItem_1);

        final JMenuItem newItemMenuItem_2 = new JMenuItem();
        newItemMenuItem_2.setText("邮箱");
        menu.add(newItemMenuItem_2);

        final JMenu menu_1 = new JMenu();
        menu_1.setText("会员");
        menu.add(menu_1);

        final JMenuItem newItemMenuItem_3 = new JMenuItem();
        newItemMenuItem_3.setText("会员官网");
        menu_1.add(newItemMenuItem_3);

        final JMenuItem newItemMenuItem_4 = new JMenuItem();
        newItemMenuItem_4.setText("会员专区");
        menu_1.add(newItemMenuItem_4);

        menu.addSeparator();

        final JMenu menu_2 = new JMenu();
        menu_2.setText("安全");
        menu.add(menu_2);

        final JMenuItem newItemMenuItem_5 = new JMenuItem();
        newItemMenuItem_5.setText("紧急冻结");
        menu_2.add(newItemMenuItem_5);

        final JMenuItem newItemMenuItem_6 = new JMenuItem();
        newItemMenuItem_6.setText("密码保护");
        menu_2.add(newItemMenuItem_6);

        final JMenuItem newItemMenuItem_7 = new JMenuItem();
        newItemMenuItem_7.setText("退出");
        menu.add(newItemMenuItem_7);
        final FlowLayout flowLayout_1 = new FlowLayout();
        flowLayout_1.setAlignment(FlowLayout.RIGHT);

        this.addWindowListener(new WindowAdapter() {
            @Override
            public void windowClosing(WindowEvent e) {
                disconnect();
                System.exit(0);
            }
        });

        // 调用傻傻的等待接收列表信息
        new Thread(new WaitingReceive()).start();
        // 双击激活聊天对话框
        list.addMouseListener(new MouseAdapter() {
            @Override
            public void mouseClicked(MouseEvent e) {
                if (e.getClickCount() == 2) {
                    new ChatFrame(s);
                }
            }
        });

    }

    public void disconnect() {
        try {
            if (dos != null)
                dos.close();
            if (dis != null)
                dis.close();
            if (s != null)
                s.close();
        } catch (IOException e) {
            e.printStackTrace();
        }
    }

    class WaitingReceive implements Runnable {

        @Override
        public void run() {
            try {
                while (connected) {
                    String name = dis.readUTF();
                    System.out.println(name);
                    int flag=0;
                    for (int i = 0; i < names.size(); i++) {
                        if (name.equals(names.get(i))) {
                            flag=1;
                        }
                    }
                    if(flag==0) {
                        names.add(name);
                    }
                    list.setListData(names);
                }
            } catch (SocketException e) {
                System.out.println("a client has been closed!");
            } catch (IOException e) {
                e.printStackTrace();
            }
        }
    }

    /**
     * WindowBuilder generated method.<br>
     * Please don‘t remove this method or its invocations.<br>
     * It used by WindowBuilder to associate the {@link javax.swing.JPopupMenu} with
     * parent.
     */
    private static void addPopup(Component component, final JPopupMenu popup) {
        component.addMouseListener(new MouseAdapter() {
            public void mousePressed(MouseEvent e) {
                if (e.isPopupTrigger())
                    showMenu(e);
            }

            public void mouseReleased(MouseEvent e) {
                if (e.isPopupTrigger())
                    showMenu(e);
            }

            private void showMenu(MouseEvent e) {
                popup.show(e.getComponent(), e.getX(), e.getY());
            }
        });
    }
}