把自己曾经写的一个客户间聊天的程序与大家分享(2)

package Client;

import java.awt.*;
import java.awt.event.*;
import javax.swing.*;
import java.net.*;
import java.io.*;
import org.jvnet.substance.skin.*;

/**
 * 负责连接服务器
 * @author lijiapeng
 *
 */
public class Client extends JFrame{
	private JMenuBar menuBar=new JMenuBar();
	private JMenu system=new JMenu("系统");
	private JMenuItem exit=new JMenuItem("退出");
	private JTextArea text=new JTextArea();
	private JPanel panel=new JPanel();
    private String serverName;
 	private Socket socket;
	private Login login;

	public Client(String serverName){
		super("客户端");
		this.serverName=serverName;	
		setJMenuBar(menuBar);
		menuBar.add(system);
		system.add(exit);
		panel.setLayout(new BorderLayout());
		panel.add(text);
		add(panel);	
		setSize(200,150);
		setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
		//设置窗口的位置居中
        Dimension screenSize = Toolkit.getDefaultToolkit().getScreenSize();
        Dimension frameSize = getSize();
        if (frameSize.height > screenSize.height) {
           frameSize.height = screenSize.height;
        }
        if (frameSize.width > screenSize.width) {
           frameSize.width = screenSize.width;
        } 
        setLocation((screenSize.width - frameSize.width) / 2, (screenSize.height - frameSize.height) / 2);     			
        try{
            UIManager.setLookAndFeel("org.jvnet.substance.skin.SubstanceFieldOfWheatLookAndFeel");
        }catch(Exception  ex){
            ex.printStackTrace();           
        }	
		setVisible(true);
		exit.addActionListener(new ActionListener(){
			public void actionPerformed(ActionEvent e){
				System.exit(0);
			}
		});
	}

	/**
	 * 与服务器取得连接
	 */
	public void getConnection(){
		try{
			text.setText("连接中...");
			socket=new Socket(InetAddress.getByName(serverName),4000);
			if(!socket.isConnected()){
	        	closeConnection();
	        }
			String name=socket.getInetAddress().getHostName();
			text.append("\n成功连接到服务器"+name);
		   	login=new Login(socket,serverName,4000);
		   	this.setVisible(false);
		   	login.setVisible(true);
		}catch(Exception e1){
			e1.printStackTrace();
		}
	}	

    public void closeConnection()throws IOException{
    	socket.close(); 	
    }	

	/**
	 * 主函数
	 */
	public static void main(String args[]){
     	Client client;
     	if(args.length==0)
     	   client=new Client("127.0.0.1");
     	else
     	    client=new Client(args[0]);
     	client.getConnection();	
	}
}