java实现最基础的socket网络通信

import java.net.*;
import java.io.*;
/**
手机端代码
手机端作为服务器，获取自己的ip地址，并显示以供客户端连接
*/
public class phone_Server
{
    public static void main(String[] args)
        throws IOException
    {
        //打印本机的IP地址
        InetAddress address=InetAddress.getLocalHost();
        System.out.println("本机的IP地址是"+address.getHostAddress());
        // 创建一个ServerSocket，用于监听客户端Socket的连接请求
        ServerSocket ss = new ServerSocket(30000);
        // 采用循环不断接受来自客户端的请求
        while (true)
        {
            // 每当接受到客户端Socket的请求，服务器端也对应产生一个Socket
            Socket s = ss.accept();
            // 将Socket对应的输出流包装成PrintStream
            PrintStream ps = new PrintStream(s.getOutputStream());
            // 进行普通IO操作
            ps.println("您好，您收到了服务器的新年祝福！");
            // 关闭输出流，关闭Socket
            ps.close();
            s.close();
        }
    }
}

/**
PC端代码
PC作为客户端，根据服务器的IP地址和端口号连接服务器
*/
import java.net.*;
import java.io.*;

public class PC_Client
{
    public static void main(String[] args)
        throws IOException
    {
        //Socket socket = new Socket("127.0.0.1" , 30000);
        Socket socket = new Socket("192.168.47.1" , 30000);//这里的IP地址填写手机端服务器的IP地址
        // 将Socket对应的输入流包装成BufferedReader
        BufferedReader br = new BufferedReader(new InputStreamReader(socket.getInputStream()));
        // 进行普通IO操作
        String line = br.readLine();
        System.out.println("来自服务器的数据：" + line);
        // 关闭输入流、socket
        br.close();
        socket.close();
    }
}

            DataOutputStream out = new DataOutputStream(socket.getOutputStream());
                int start=0;
                while((start+1024)<data.length)
                {
                    out.write(data, start,1024);
                    start=start+1024;
                }
                if(start<data.length)
                {
                    out.write(data, start,(data.length-start+1));
                }
                //String str = new String(data);
                //out.writeUTF(str);
            }catch (Exception e) {
                Log.d(TAG, "文件传输异常");
            }

        DataInputStream input = new DataInputStream(socket.getInputStream());
        byte []buf=new byte[1024];
        int readnum=0;
        while(true)
        {
            readnum=input.read(buf); 
            if(readnum>0)
            {
                System.out.println(Arrays.toString(buf));

                while((readnum=input.read(buf))>0)
                {
                    System.out.println(Arrays.toString(buf));
                }
            }
        }