文件上传

服务器端

package programming;

import java.io.*;
import java.net.ServerSocket;
import java.net.Socket;

public class TcpServer1 {
    public static void main(String[] args) throws IOException {
        //1.创建服务
        ServerSocket serverSocket = new ServerSocket(9000);
        //2.监听客户端的连接
        Socket socket = serverSocket.accept();//阻塞式监听，会一直等待客户端连接
        //3.获取输入流
        InputStream is = socket.getInputStream();
       // 4.文件输出
        FileOutputStream fos = new FileOutputStream(new File("receive.jpg"));
        byte[] buffer = new byte[1024];
        int len;
        while ((len = is.read(buffer))!= -1){
            fos.write(buffer,0,len);
        }
        //通知客户端我接收完毕了
        OutputStream os = socket.getOutputStream();
        os.write("接收已完成".getBytes());
        fos.close();
        is.close();
        socket.close();
        serverSocket.close();
    }
}

客户端

package programming;

import java.io.*;
import java.net.InetAddress;
import java.net.Socket;
import java.net.UnknownHostException;

public class TcpClient1 {
    public static void main(String[] args) throws Exception {
        //1.创建一个Socket连接
        Socket socket = new Socket(InetAddress.getByName("127.0.0.1"),9000);
        //2.创建一个输出流
        OutputStream os = socket.getOutputStream();
       // 3.读取文件
        FileInputStream fis = new FileInputStream(new File("a.jpg"));
        //4.将文件内容写入输出流
        byte[] buffer = new byte[1024];
        int len;
        while ((len = fis.read(buffer))!= -1){
            os.write(buffer,0,len);
        }
        //通知服务器，文件发送完毕
        socket.shutdownOutput();//我已经传输完毕了
        //确定服务器接收完毕，才能断开连接
        InputStream inputStream = socket.getInputStream();
        ByteArrayOutputStream baos = new ByteArrayOutputStream();
        byte[] buffer1 = new byte[1024];
        int len1;
        while ((len1 = inputStream.read(buffer1))!= -1){
            baos.write(buffer1,0,len1);
        }
        System.out.println(baos.toString());
        //5.关闭资源
        inputStream.close();
        baos.close();
        fis.close();
        os.close();
        socket.close();
    }
}