eclipse 中编了个聊天室服务器端 如何跑不起来

import java.awt.BorderLayout;
import java.awt.FlowLayout;
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.ServerSocket;
import java.net.Socket;
import java.util.ArrayList;
import java.util.List;

import javax.swing.JButton;
import javax.swing.JFrame;
import javax.swing.JOptionPane;
import javax.swing.JPanel;
import javax.swing.JScrollPane;
import javax.swing.JTextArea;
import javax.swing.JTextField;
/*这个类是服务器端的UI*/
public class myServer extends JFrame {
  	
	static JButton btStart;//启动服务器
	static JButton btSend;//发送信息按钮
	static JTextField tfSend;//需要发送的文本信息
	static JTextArea taShow;//信息展示
	static Server server;//用来监听客户端连接
    static List<Socket> clients;//保存连接到服务器的客户端
    public myServer() {
        setTitle("服务器");
        
        btStart = new JButton("启动服务");
        btSend = new JButton("发送信息");
        tfSend = new JTextField(10);
        taShow = new JTextArea();

        btStart.addActionListener(new ActionListener() {
            public void actionPerformed(ActionEvent e) {
                server = new Server(myServer.this);
            }
        });
        btSend.addActionListener(new ActionListener() {
            public void actionPerformed(ActionEvent e) {
                server.sendMsg(tfSend.getText());
                tfSend.setText("");
            }
        });
        this.addWindowListener(new WindowAdapter() {
            public void windowClosing(WindowEvent e) {
                int a = JOptionPane.showConfirmDialog(null, "确定关闭吗？", "温馨提示",
                        JOptionPane.YES_NO_OPTION);
                if (a == 1) {
                    server.closeServer();
                    System.exit(0); // 关闭