java实现一个窗口

 
    import java.awt.BorderLayout;
import java.awt.Color;
import java.awt.GridLayout;
import java.awt.Toolkit;
import java.awt.event.ActionEvent;
import java.awt.event.ActionListener;
import java.awt.event.WindowAdapter;
import java.awt.event.WindowEvent;
import java.io.BufferedReader;
import java.io.IOException;
import java.io.InputStreamReader;
import java.io.PrintWriter;
import java.net.BindException;
import java.net.ServerSocket;
import java.net.Socket;
import java.util.ArrayList;
import java.util.StringTokenizer;

import javax.swing.DefaultListModel;
import javax.swing.JButton;
import javax.swing.JFrame;
import javax.swing.JLabel;
import javax.swing.JList;
import javax.swing.JOptionPane;
import javax.swing.JPanel;
import javax.swing.JScrollPane;
import javax.swing.JSplitPane;
import javax.swing.JTextArea;
import javax.swing.JTextField;
import javax.swing.border.TitledBorder;

public class Server {

    private JFrame frame;
    private JTextArea contentArea;
    private JTextField txt_message;
    private JTextField txt_max;
    private JTextField txt_port;
    private JButton btn_start;
    private JButton btn_stop;
    private JButton btn_send;
    private JPanel northPanel;
    private JPanel southPanel;
    private JScrollPane rightPanel;
    private JScrollPane leftPanel;
    private JSplitPane centerSplit;
    private JList userList;
    private DefaultListModel listModel;

    private ServerSocket serverSocket;
    private ServerThread serverThread;
    private ArrayList<ClientThread> clients;

    private boolean isStart = false;

    // 主方法,程序执行入口
    public static void main(String[] args) {
        new Server();
    }
public Server() {
        frame = new JFrame("服务器");
        // 更改JFrame的图标：
        //frame.setIconImage(Toolkit.getDefaultToolkit().createImage(Client.class.getResource("qq.png")));
        frame.setIconImage(Toolkit.getDefaultToolkit().createImage(Server.class.getResource("qq.png")));
        contentArea = new JTextArea();
        contentArea.setEditable(false);
        contentArea.setForeground(Color.blue);
        txt_message = new JTextField();
        txt_max = new JTextField("30");
        txt_port = new JTextField("6666");
        btn_start = new JButton("启动");
        btn_stop = new JButton("停止");
        btn_send = new JButton("发送");
        btn_stop.setEnabled(false);
        listModel = new DefaultListModel();
        userList = new JList(listModel);

        southPanel = new JPanel(new BorderLayout());
        southPanel.setBorder(new TitledBorder("写消息"));
        southPanel.add(txt_message, "Center");
        southPanel.add(btn_send, "East");
        leftPanel = new JScrollPane(userList);
        leftPanel.setBorder(new TitledBorder("在线用户"));

        rightPanel = new JScrollPane(contentArea);
        rightPanel.setBorder(new TitledBorder("消息显示区"));

        centerSplit = new JSplitPane(JSplitPane.HORIZONTAL_SPLIT, leftPanel,
                rightPanel);
        centerSplit.setDividerLocation(100);
        northPanel = new JPanel();
        northPanel.setLayout(new GridLayout(1, 6));
        northPanel.add(new JLabel("人数上限"));
        northPanel.add(txt_max);
        northPanel.add(new JLabel("端口"));
        northPanel.add(txt_port);
        northPanel.add(btn_start);
        northPanel.add(btn_stop);
        northPanel.setBorder(new TitledBorder("配置信息"));

        frame.setLayout(new BorderLayout());
        frame.add(northPanel, "North");
        frame.add(centerSplit, "Center");
        frame.add(southPanel, "South");
        frame.setSize(600, 400);
        //frame.setSize(Toolkit.getDefaultToolkit().getScreenSize());//设置全屏
        int screen_width = Toolkit.getDefaultToolkit().getScreenSize().width;
        int screen_height = Toolkit.getDefaultToolkit().getScreenSize().height;
        frame.setLocation((screen_width - frame.getWidth()) / 2,
                (screen_height - frame.getHeight()) / 2);
        frame.setVisible(true);
}