Socket通信简单例子

服务端Server：

package com.test;
import java.io.IOException;
import java.io.OutputStream;
import java.net.ServerSocket;
import java.net.Socket;
public class Server {
	public static void main(String[] args) throws IOException {
		ServerSocket server = new ServerSocket(8888);
		Socket socket = server.accept();
		OutputStream out = socket.getOutputStream();
		String msg = "Hello";
		out.write(msg.getBytes());
		socket.close();
	}
}

用程序完成telnet功能：(客户端Client)

package com.test;
import java.io.IOException;
import java.io.InputStream;
import java.net.Socket;
import java.net.UnknownHostException;
public class Client {
	public static void main(String[] args) throws UnknownHostException, IOException {
		Socket socket = new Socket("127.0.0.1", 8888);
		InputStream in = socket.getInputStream();
		byte[] buffer = new byte[in.available()];
		in.read(buffer);
		String msg = new String(buffer);
		System.out.println("收到响应信息 >>> "+msg);
	}
}

输出：

收到响应信息 >>> Hello

-------------------------------------------------------------------------------------------------------------------------------------------------------

下面给一个更全面的例子：

Server:

package com.test;

import java.io.BufferedReader;
import java.io.BufferedWriter;
import java.io.IOException;
import java.io.InputStreamReader;
import java.io.OutputStreamWriter;
import java.io.PrintWriter;
import java.net.ServerSocket;
import java.net.Socket;

public class Server {
	public static int PORT = 8888;

	public static void main(String[] args) throws IOException {
		ServerSocket server = null;
		Socket client = null;
		BufferedReader br = null;
		PrintWriter pw = null;
		try {
			server = new ServerSocket(PORT);
			client = server.accept();
			br = new BufferedReader(new InputStreamReader(client.getInputStream()));
			pw = new PrintWriter(new BufferedWriter(new OutputStreamWriter(client.getOutputStream())));
			while (true) {
				String msg = br.readLine();
				if (msg.equals("END")) {
					break;
				}
				System.out.println("收到Client消息：" + msg);
				Thread.sleep(1000);
				pw.println("Message Received");
				pw.flush();
			}
		} catch (Exception e) {
			e.printStackTrace();
		} finally {
			System.out.println("Server Close.....");
			try {
				br.close();
				pw.close();
				client.close();
				server.close();
			} catch (IOException e) {
				e.printStackTrace();
			}
		}
	}
}

最终输出：

收到Client消息：Msg 0
收到Client消息：Msg 1
收到Client消息：Msg 2
收到Client消息：Msg 3
收到Client消息：Msg 4
收到Client消息：Msg 5
收到Client消息：Msg 6
收到Client消息：Msg 7
收到Client消息：Msg 8
收到Client消息：Msg 9
Server Close.....

Client:

package com.test;

import java.io.BufferedReader;
import java.io.BufferedWriter;
import java.io.IOException;
import java.io.InputStreamReader;
import java.io.OutputStreamWriter;
import java.io.PrintWriter;
import java.net.Socket;
import java.net.UnknownHostException;

public class Client {
	public static void main(String[] args) throws UnknownHostException, IOException {
		Socket socket = null;
		BufferedReader br = null;
		PrintWriter pw = null;
		try {
			socket = new Socket("127.0.0.1", Server.PORT);
			System.out.println("Socket = " + socket);
			br = new BufferedReader(new InputStreamReader(socket.getInputStream()));
			pw = new PrintWriter(new BufferedWriter(new OutputStreamWriter(socket.getOutputStream())));
			for (int i = 0; i < 10; i++) {
				pw.println("Msg " + i);
				pw.flush();
				String str = br.readLine();
				System.out.println("收到Server响应：" + str);
			}
			pw.println("END");
			pw.flush();
		} catch (Exception e) {
			e.printStackTrace();
		} finally {
			try {
				System.out.println("Client close......");
				br.close();
				pw.close();
				socket.close();
			} catch (IOException e) {
				e.printStackTrace();
			}
		}
	}
}

最终输出：

Socket = Socket[addr=/127.0.0.1,port=8888,localport=54091]

收到Server响应：Message Received
收到Server响应：Message Received
收到Server响应：Message Received
收到Server响应：Message Received
收到Server响应：Message Received
收到Server响应：Message Received
收到Server响应：Message Received
收到Server响应：Message Received
收到Server响应：Message Received
收到Server响应：Message Received
Client close......