tcp通讯_一个服务器可以给多个客户端发送图片

服务端

package com.cn.tcp;
import java.io.File;
import java.io.FileInputStream;
import java.io.IOException;
import java.io.OutputStream;
import java.net.ServerSocket;
import java.net.Socket;
import java.util.HashSet;
/**
 * 编写一个服务端可以给多个客户端发送图片。（多线程）
 * @author zhiyong
 *
 */
/**
 * 服务端
 * @author zhiyong
 *
 */
public class ImageServer extends Thread{
  Socket socket = null;
  //使用该集合是用于存储ip地址的， 注意共享
  static HashSet<String> ips = new HashSet<String>();
  
  public ImageServer(Socket socket) {
    this.socket = socket;
  }
  public void run() {
    try {
      //获取到socket的输出流对象
      OutputStream outputStream = socket.getOutputStream();
      //获取图片的输入流对象
      FileInputStream fileInputStream = new FileInputStream(new File("f:/cool.png"));
      //读取图片数据，把数据写出
      byte[] buf = new byte[1024];
      int length = 0;
      while((length = fileInputStream.read(buf)) != -1){
        outputStream.write(buf, 0, length);
      }
      
      String ip = socket.getInetAddress().getHostAddress();//socket.getInetAddress()获取对方的ip地址对象
      System.out.println("下载的ip是：" + ip);
      if(ips.add(ip)){
        System.out.println("恭喜" +  ip + "用户成功下载！当前下载人数是：" + ips.size());
      }
        
      //关闭资源
      fileInputStream.close();
      socket.close();
    }  catch (IOException e) {
      // TODO Auto-generated catch block
      e.printStackTrace();
    }
  }
  
  public static void main(String[] args) throws IOException {
    //建立tcp服务端，并且要监听一个端口
    ServerSocket serverSocket = new ServerSocket(9090); 
    while(true){//不断接收用户的连接
      Socket socket = serverSocket.accept();
      new ImageServer(socket).start();//启动多线程
    }
    
  }
}

客户端

package com.cn.tcp;
import java.io.File;
import java.io.FileOutputStream;
import java.io.IOException;
import java.io.InputStream;
import java.net.InetAddress;
import java.net.Socket;
import java.net.UnknownHostException;
/**
 * 下载图片的客户端
 * @author zhiyong
 *
 */
public class ImageClient {
  public static void main(String[] args) throws IOException, IOException {
    System.out.println(InetAddress.getLocalHost());
    //建立tcp服务
    Socket socket = new Socket(InetAddress.getByName("192.168.18.111"), 9090);
    //获取socket的输入流对象
    InputStream inputStream = socket.getInputStream();
    //获取文件的输出流对象，为了把获取到的文件写出
    FileOutputStream fileOutputStream = new FileOutputStream(new File("f:/jj.png"));
    //边读编写
    byte[] buf = new byte[1024];
    int length = 0;
    while((length = inputStream.read(buf)) != -1){
      fileOutputStream.write(buf, 0, length);
    }
    //关闭资源
    fileOutputStream.close();
    socket.close();   
  }
}