客户端代码:

package com.kaige123.net01; import java.io.IOException; import java.io.InputStream; import java.io.OutputStream; import java.net.Socket; import java.net.UnknownHostException; /***凯哥*/ public class Client { public static void main(String[] args) throws Exception { // 如果对方服务器不存在就会报错 Socket socket = new Socket("127.0.0.1", 8080); 		InputStream input = socket.getInputStream();		OutputStream output = socket.getOutputStream();				output.write("你好服务器，我是凯哥，你还记得我吗？".getBytes());		output.flush();//赶紧把内容输出到对方 byte[] b=new byte[1024]; int len=input.read(b);		System.out.println("服务器说:"+new String(b,0,len));				output.close();		input.close();		socket.close();			}}

服务端代码:

package com.kaige123.net01; import java.io.IOException; import java.io.InputStream; import java.io.OutputStream; import java.net.ServerSocket; import java.net.Socket; /***凯哥*/ public class Server{ public static void main(String[] args) throws Exception { // 如果都被占用 那就会抛异常 // 建立好一个服务端 监听8080端口 ServerSocket server = new ServerSocket(8080); // 等待客户端来连接服务器 Socket socket = server.accept(); //代码运行到这句就会卡主 堵塞  等待 InputStream input = socket.getInputStream();		OutputStream output = socket.getOutputStream(); byte[] b = new byte[1024 * 5]; int len = input.read(b);		String s = new String(b, 0, len);		System.out.println(s);		s = "你好凯哥，我是从东莞回来的美女!!";		output.write(s.getBytes());				output.close();		input.close();		socket.close();	}}

TCP简单通讯