注意：網路程式設計的正常步驟先跑服務端，再跑客戶端； 第一步先用eclipse執行server端；

第二步用命令列執行客戶端；

檢視結果：

把檔案copy出去改下字尾，發現檔案可以開啟

package cn.njit.internet.fileUpload;

import java.io.BufferedInputStream; import java.io.FileOutputStream; import java.io.IOException; import java.io.InputStream; import java.net.ServerSocket; import java.net.Socket;

/*******

• 檔案上傳
• TCP實現-服務端
• @author Administrator

*/ public class Server {

public static void main(String[] args) throws IOException {
	int port=9999;
	ServerSocket ss=new ServerSocket(port);
	Socket cs=ss.accept();
	
	ServerThread st=new ServerThread(cs);
	st.start();
	
	
}

}

class ServerThread extends Thread{ Socket socket; String fileName; int i=(int) (Math.random()*10000000+1000000); public ServerThread(Socket socket) { this.socket=socket; this.fileName=String.valueOf(i); } public void run() { doFileUpload(); } private void doFileUpload() {

	try {
		InputStream is=socket.getInputStream();
		BufferedInputStream bis=new BufferedInputStream(is);
		byte[] buf=new byte[1024];
		int len=bis.read(buf);
		fileName="D:\\First\\Second\\"+fileName;
		
		
		
		//實現斷點續傳
		while(-1!=len) {
			FileOutputStream fos=new FileOutputStream(fileName,true);
			fos.write(buf,0,len);
			fos.close();
			len=bis.read(buf);	
		}
		
		
	/*	FileOutputStream fos=new FileOutputStream(fileName,true);	
	 * while(-1!=len) {
			fos.write(buf,0,len);	
			len=bis.read(buf);	
		}
		fos.close();
	*/
	
		bis.close();
		
		
	} catch (IOException e) {
		System.out.println(e.getMessage());
	}
	
}
 

}

package cn.njit.internet.fileUpload;

import java.io.FileInputStream; import java.io.IOException; import java.io.InputStream; import java.io.OutputStream; import java.net.Socket;

/*******

• 檔案上傳
• TCP實現-客戶端
• @author Administrator

*/ public class Client {

public static void main(String[] args) throws Exception, IOException {
	if(args.length<1) {
		System.out.println("請輸入檔案路徑!");
		return;
	}
	String fileName=args[0];
	
	String serverHost="localhost";
	int port =9999;
	Socket socket=new Socket(serverHost,port);
	
	OutputStream os=socket.getOutputStream();
	InputStream is=new FileInputStream(fileName);
	
	byte[] buf=new byte[1024];
	int len=is.read(buf);
	while(-1!=len) {
		os.write(buf,0,len);
		len=is.read(buf);
	}
	
	is.close();
	os.close();	
	socket.close();
}

}

end； 2018.09.30；