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();

	}

}