Java中利用网络编程和多线程上传文件

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一、要求

二、代码示例

1、客户端

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

public class Client {
    public static void main(String[] args) throws IOException {
        //客户端：将本地文件上传到服务器，接收服务器的反馈
        //服务器：接收客户端上传的文件，上传完毕后给出反馈

        //1.创建Socket对象，并连接服务器
        Socket socket = new Socket("127.0.0.1",10086);

        //2.读取本地文件中的数据，并写到服务器中
        BufferedInputStream bis = new BufferedInputStream(new FileInputStream("D:\\Java\\mysocketent\\clientdir\\a.jpg"));
        BufferedOutputStream bos = new BufferedOutputStream(socket.getOutputStream());
        byte[] bytes = new byte[1024];
        int len;
        while ((len = bis.read(bytes)) != -1){
            bos.write(bytes,0,len);
        }

        //往服务器写出结束标记
        socket.shutdownOutput();

        //3.接收服务器的回写数据
        BufferedReader br = new BufferedReader(new InputStreamReader(socket.getInputStream()));
        String line = br.readLine();
        System.out.println(line);


        //4.释放资源
        socket.close();
    }
}

2、服务器代码

import java.io.IOException;
import java.net.ServerSocket;
import java.net.Socket;
import java.util.concurrent.ArrayBlockingQueue;
import java.util.concurrent.Executors;
import java.util.concurrent.ThreadPoolExecutor;
import java.util.concurrent.TimeUnit;

public class Server {
    public static void main(String[] args) throws IOException {
        //创建线程池对象
        ThreadPoolExecutor pool = new ThreadPoolExecutor(
                3,//核心线程数量
                16, //线程池总大小
                60,  //空闲时间
                TimeUnit.SECONDS,//空闲时间（单位）
                new ArrayBlockingQueue<>(2),//队列
                Executors.defaultThreadFactory(),//线程工厂，让线程池如何创建线程对象
                new ThreadPoolExecutor.AbortPolicy()//阻塞队列
        );
        //1.创建对象并绑定端口
        ServerSocket ss = new ServerSocket(10086);

        while (true) {
            //2.等待客户端连接
            Socket socket = ss.accept();

            //开启一条线程
            // 一个用户就对应服务端的一条线程
            //new Thread((new MyRunnable(socket))).start();
            pool.submit(new MyRunnable(socket));
        }

    }
}

3、线程池

import java.io.*;
import java.net.Socket;
import java.util.UUID;

public class MyRunnable implements Runnable{

    Socket socket;

    public MyRunnable (Socket socket){
        this.socket = socket;
    }

    @Override
    public void run() {
        try {
            //3.读取数据并保存到本地文件中
            BufferedInputStream bis = new BufferedInputStream(socket.getInputStream());
            String name = UUID.randomUUID().toString().replace("-","");
            BufferedOutputStream bos = new BufferedOutputStream(new FileOutputStream("D:\\Java\\mysocketent\\serverdir\\"+name+".jpg"));
            int len;
            byte[] bytes = new byte[1024];
            while ((len = bis.read(bytes)) != -1){
                bos.write(bytes,0,len);
            }
            //4.回写数据
            BufferedWriter bw = new BufferedWriter(new OutputStreamWriter(socket.getOutputStream()));
            bw.write("上传成功");
            bw.newLine();
            bw.flush();
        } catch (IOException e) {
            e.printStackTrace();
        } finally {
            //5.释放资源
            if(socket != null ){
                try {
                    socket.close();
                } catch (IOException e) {
                    e.printStackTrace();
                }
            }
        }
    }
}

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