一、概述

1.目标：建立基于tcp协议的聊天系统

2.思路：用java socket编程

二、代码

1.ChatServer.java

import java.io.DataInputStream;

import java.io.EOFException;

import java.io.IOException;

import java.net.ServerSocket;

import java.net.Socket;

import java.net.UnknownHostException;

public class ChatServer{

public static void main(String[] args) {

DataInputStream dis = null;

Socket s = null;

ServerSocket ss = null;

boolean started =false;

try {

ss = new ServerSocket(8888);

} catch (IOException e1) {

e1.printStackTrace();

}

try {

started = true;

while(started){

boolean bConnect = false;

//!!!!!注意accept()是阻塞性方法，当被readUTF()阻塞时它不会被执行

s = ss.accept();

System.out.println("a client connect------"+s);

dis = new DataInputStream(s.getInputStream());

bConnect = true;

while(bConnect){

//!!!!!注意readUTF()是阻塞性方法

System.out.println(dis.readUTF());

}

}

} catch (EOFException e) {

System.out.println("客户端已关闭！");

} catch (IOException e) {

e.printStackTrace();

}finally{

try {

if(dis != null ) dis.close();

if(s != null ) s.close();

if(ss != null ) ss.close();

} catch (Exception e) {

e.printStackTrace();

}

}

}

}

2.Chatclient.java

import java.awt.BorderLayout;

import java.awt.Button;

import java.awt.Frame;

import java.awt.TextArea;

import java.awt.TextField;

import java.awt.event.ActionEvent;

import java.awt.event.ActionListener;

import java.awt.event.KeyEvent;

import java.awt.event.WindowAdapter;

import java.awt.event.WindowEvent;

import java.io.DataOutputStream;

import java.io.IOException;

import java.io.OutputStream;

import java.net.Socket;

import java.net.UnknownHostException;

public class ChatClient extends Frame{

private TextField tfText;

private TextArea taContent;

//private Button btnSend;

private Socket socket;

private DataOutputStream dos;

public void launchFrame(){

addWindowListener(new WindowAdapter() {

public void windowClosing(WindowEvent e) {

disconnect();

System.exit(0);

}

});

tfText = new TextField();

taContent = new TextArea();

//btnSend = new Button("发送");

//

//btnSend.addActionListener(new ActionListener() {

//@Override

//public void actionPerformed(ActionEvent e) {

taContent.setText(taContent.getText()+"\n\r"+tfText.getText());

tfText.setText("");

//try {

//DataOutputStream dos = new DataOutputStream(socket.getOutputStream());

//dos.writeUTF(tfText.getText());

//dos.close();

//socket.close();

//} catch (IOException e1) {

//e1.printStackTrace();

//}

//}

//});

tfText.addActionListener(new TFListener());

add(taContent,BorderLayout.NORTH);

add(tfText,BorderLayout.CENTER);

//add(btnSend,BorderLayout.SOUTH);

setLocation(300, 100);

pack();

setVisible(true);

connect("localhost", 8888);

}

//当调用了此方法，会自动把成员变量给socket连接上server

public void connect(String address, int port){

try {

socket = new Socket(address, port);

dos = new DataOutputStream(socket.getOutputStream());

} catch (UnknownHostException e) {

e.printStackTrace();

} catch (IOException e) {

e.printStackTrace();

}

}

//退出时释放资源

public void disconnect(){

try {

if(dos != null ) dos.close();

if(socket != null ) socket.close();

} catch (IOException e) {

e.printStackTrace();

}

}

class TFListener implements ActionListener{

@Override

public void actionPerformed(ActionEvent e) {

taContent.setText(taContent.getText().trim()+"\n\r"+tfText.getText());

try {

dos.writeUTF(tfText.getText());

dos.flush();

tfText.setText("");

//dos.close();

//socket.close();

} catch (IOException e1) {

e1.printStackTrace();

}

}

}

public static void main(String[] args) {

new ChatClient().launchFrame();

}

}

三、运行结果