服務端程式碼

package com.cyj.tcp.chat2;

import java.io.DataInputStream;
import java.io.DataOutputStream;
import java.io.IOException;
import java.net.ServerSocket;
import java.net.Socket;
import java.util.ArrayList;
import java.util.List;

/**
 * 建立伺服器，可以接收多個客戶端
 * @author Chyjrily
 *
 */
public class Server {
	
	private List<Channel> all = new ArrayList<Channel>(); //通過容器，管理管理其他的管道，轉發時只需遍歷容器
	
	public static void main(String[] args) throws IOException {
	
	new Server().start(); //呼叫下面的方法，呼叫靜態方法
    
}
	
	public void start() throws IOException {
	    ServerSocket server = new ServerSocket(2500);  
		
	    while(true) {
			Socket client = server.accept();  
			Channel ch = new Channel(client); //建立一條通道
			all.add(ch); //將自己加入容器
			new Thread(ch).start(); //啟動分配管道的多執行緒
		}	
	}
	       

	
   //每個客戶端分配一條道路
   class Channel implements Runnable{
	   
	   private DataInputStream dis;
	   private DataOutputStream dos;
	   private boolean isRunning = true;
	   
	   public Channel(Socket client) throws IOException{
		   try {
			dis = new DataInputStream(client.getInputStream());
			dos =new DataOutputStream(client.getOutputStream());
		   
		} catch (IOException e) {
			dis.close();
			dos.close();
			isRunning = false;
		 }
	   }
	   
	   
	   //讀取資料
	   private String receive() {
		   String msg = ""; 
		   try {
			msg = dis.readUTF();
		} catch (IOException e) {
			all.remove(this);//管道出現異常，移除出容器
		} 
		   return msg;
	   }
	   
	   //傳送資料
	   private void send(String msg){
		   if(null==msg || msg.equals("")) {
			   return;
		   }
		   try {
			dos.writeUTF(msg);
			dos.flush();
		} catch (IOException e) {
			all.remove(this);//管道出現異常，移除出容器
		}  
	   }
	   
	   
	   //轉發內容給其他的客戶端 
	   private void sendOthers() {
		   String msg = receive();
		   
		   //遍歷容器
		   for(Channel other:all) {
			   if(other == this) {
				   continue;
			   }
			   //轉發
			   other.send(msg);
		   }
	   }
	   
	   public void run() {
		   while(isRunning) {
			   sendOthers();
		   }
	   }
   }
}
 

客戶端程式碼

package com.cyj.tcp.chat2;

import java.io.IOException;
import java.net.Socket;
import java.net.UnknownHostException;

/**
 * 客戶端可以傳送和接收資料，且相互獨立
 * 資料的接收和傳送不能夠有先後順序
 * @author Chyjrily
 *
 */
public class Client {

	public static void main(String[] args) throws UnknownHostException, IOException {
		Socket client = new Socket("DESKTOP-BEUJ3C4",2500);
		
		new Thread(new Send(client)).start();     //呼叫傳送資料的多執行緒
		new Thread(new Receive(client)).start();  //呼叫接收資料的多執行緒

	}
	
}
 

接收資料建立的多執行緒

package com.cyj.tcp.chat2;

import java.io.BufferedReader;
import java.io.DataInputStream;
import java.io.DataOutputStream;
import java.io.IOException;
import java.net.Socket;

/**
 * 接收執行緒
 * @author Chyjrily
 *
 */
public class Receive implements Runnable {
	
	private boolean isRunning = true;
	
	//管道輸入流 
	private DataInputStream dis;
	
	public Receive() {
			
	}
	
	public Receive(Socket client) throws IOException {
		try {
			dis = new DataInputStream(client.getInputStream());
		} catch (IOException e) {
			isRunning = false;
			dis.close();
		}	
	}
	
	public String receive() throws IOException {
		while(true) {
			String msg = "沒有接收到資料";
			dis.readUTF();
			return msg;
		}
	}
	
	public void run(){
		while(isRunning) {
			try {
				System.out.println(receive());
			} catch (IOException e) {
				e.printStackTrace();
				System.out.println("接收失敗");
			}
		}
	}
	
}
 

傳送資料建立的多執行緒

package com.cyj.tcp.chat2;

import java.io.BufferedReader;
import java.io.DataOutputStream;
import java.io.IOException;
import java.io.InputStreamReader;
import java.net.Socket;

/**
 * 通過多執行緒，將客戶端的資料的傳送與資料的接收想一致
 * @author Chyjrily
 *
 */
public class Send implements Runnable {

	//控制檯輸入流
	private BufferedReader console;
	
	//管道輸出流
	private DataOutputStream dos;
	
	//管道是否能正常執行的標識
	private boolean isRunning = true;
	
	public Send(){
		console = new BufferedReader(new InputStreamReader(System.in));
		
	}
	
	public Send(Socket client) throws IOException{ //通過接收資料，將管道傳過來
		this();
		try {
			dos = new DataOutputStream(client.getOutputStream());
		} catch (IOException e) {
			isRunning = false; //管道是一切傳輸的基礎，如果不執行，直接終止程式
			dos.close();
			console.close();
		}
	}
	
	//從控制檯接收資料
	private String getMsg() throws IOException{
		return console.readLine();
	}
	
	public void send() throws IOException {
		String msg = getMsg();
		if(null != msg) {
			dos.writeUTF(msg);
			dos.flush();
		}
	}
	
	public void run() {
		 while(isRunning) { //是否執行的標誌
			try {
				send();
			} catch (IOException e) {
				e.printStackTrace();
				System.out.println("伺服器多執行緒啟動失敗");
			} 
		 }
	}
}