这个是我个人写代码的时候做的一些记录，错误估计很多。嘿嘿，大家看到了希望能指正
package com.aosa.test;

import java.io.DataInputStream;
import java.io.File;
import java.io.FileOutputStream;
import java.io.IOException;
import java.net.Socket;
import java.net.UnknownHostException;

public class Client {
    public static void main(String[] args) {
        try {
            
            Socket socket = new Socket("localhost", 4444);
            
            DataInputStream dataInputStream = new DataInputStream(socket.getInputStream());
            
            String fileName = dataInputStream.readUTF();
            //本地文件路径
            File file = new File("D://" + fileName);
            
            FileOutputStream fileOutputStream = new FileOutputStream(file);
            
            byte[] buffer = new byte[1024];
            
            while(dataInputStream.read(buffer) != -1){
                fileOutputStream.write(buffer);
            }
            
            dataInputStream.close();
            
            fileOutputStream.flush();
            fileOutputStream.close();
            
            socket.close();
            
        } catch (UnknownHostException e) {
            e.printStackTrace();
        } catch (IOException e) {
            e.printStackTrace();
        }
    }
}


package com.aosa.test;

import java.io.DataOutputStream;
import java.io.File;
import java.io.FileInputStream;
import java.io.IOException;
import java.net.ServerSocket;
import java.net.Socket;

public class Server {
    public static void main(String[] args) {
        
        try {
            ServerSocket serverSocket = new ServerSocket(4444);
            while(true){
                Socket socket = serverSocket.accept();
                
                File file = new File("F://JUDE(JAVA建模软件).rar");

                String fileName = file.getName();
                
                FileInputStream fileInputStream = new FileInputStream(file);
                
                DataOutputStream dataOutputStream = new DataOutputStream(socket.getOutputStream());
                //向客户端输文件
                dataOutputStream.writeUTF(fileName);
                
                byte[] buffer = new byte[1024];
                
                while(fileInputStream.read(buffer) != -1){
                    dataOutputStream.write(buffer);
                }
                
                //dataOutputStream.writeUTF("false");

                fileInputStream.close();
                
                dataOutputStream.flush();
                dataOutputStream.close();
                
                socket.close();
            }
            
        } catch (IOException e) {
            // TODO Auto-generated catch block
            e.printStackTrace();
        }
        
        
    }
}