伺服器端：

import java.io.BufferedReader;
import java.io.BufferedWriter;
import java.io.FileWriter;
import java.io.IOException;
import java.io.InputStreamReader;
import java.io.PrintWriter;
import java.net.ServerSocket;
import java.net.Socket;

//上傳伺服器檔案
public class UploadServer {

	public static void main(String[] args) throws IOException {

		System.out.println("上傳伺服器啟動了...");
		//1.建立伺服器
		ServerSocket ss=new ServerSocket(10000);
		//2.獲取socket物件
		Socket s=ss.accept();
		//列印ip地址
		String ip=s.getInetAddress().getHostAddress();
		System.out.println(ip+"...connected");
		//3.獲取輸入流輸出流
		BufferedReader br=new BufferedReader(new InputStreamReader(s.getInputStream()));
		//將接收到的檔案輸出到server.txt
		BufferedWriter bw=new BufferedWriter(new FileWriter("server.txt"));
		String line=null;
		while((line=br.readLine())!=null){
			bw.write(line);
			bw.newLine();
			bw.flush();
		}
		PrintWriter pw=new PrintWriter(s.getOutputStream(),true);
		pw.println("上傳成功");
		br.close();
		bw.close();
		pw.close();
		s.close();
		ss.close();

	}

}
 

客戶端：

import java.io.BufferedReader;
import java.io.File;
import java.io.FileNotFoundException;
import java.io.FileReader;
import java.io.IOException;
import java.io.InputStreamReader;
import java.io.OutputStream;
import java.io.PrintWriter;
import java.net.InetAddress;
import java.net.Socket;

public class UploadClient {

	public static void main(String[] args) throws IOException {
		
		System.out.println("上傳客戶端啟動...");
		//1.關聯檔案
		File file=new File("d:\\1.txt");
		//2.建立客戶端socket
		Socket s=new Socket(InetAddress.getLocalHost(),10000);
		//3.獲取輸入流輸出流
		//輸入流
		BufferedReader br=new BufferedReader(new FileReader(file));
		//輸出流
		PrintWriter pw=new PrintWriter(s.getOutputStream(),true);
		//邊讀邊寫   讀檔案中的內容寫到客戶端
		String line=null;
		while((line=br.readLine())!=null){
			pw.println(line);
		}
		//告訴伺服器，客戶端寫完了
		s.shutdownOutput();
		//4.接收客戶端傳送過來的資料
		BufferedReader br1=new BufferedReader(new InputStreamReader(s.getInputStream()));
		System.out.println(br1.readLine());
		//5.關閉流
		br.close();
		pw.close();
		br1.close();
		s.close();
	}

}
 

執行結果：

伺服器控制檯：

客戶端控制檯：

同時在指定目錄下生成了server.txt檔案。