java TCP连接之客户端向服务器上传文件

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UpdateClient.java:

import java.io.BufferedReader;
import java.io.File;
import java.io.FileInputStream;
import java.io.IOException;
import java.io.InputStreamReader;
import java.io.PrintStream;
import java.net.Socket;
import java.net.UnknownHostException;
import java.util.Scanner;

public class UpdateClient {

	/**
	 * @param args
	 * @throws IOException 
	 * @throws UnknownHostException 
	 */
	public static void main(String[] args) throws UnknownHostException, IOException {
		// 1.提示输入要上传的文件路径, 验证路径是否存在以及是否是文件夹
		File file = getFile();
		// 2.发送文件名到服务端
		Socket socket = new Socket("127.0.0.1", 6666);
		BufferedReader br = new BufferedReader(new InputStreamReader(socket.getInputStream()));
		PrintStream ps = new PrintStream(socket.getOutputStream());
		ps.println(file.getName());
		// 6.接收结果, 如果存在给予提示, 程序直接退出
		String result = br.readLine();						//读取存在后不存在的结果
		if("存在".equals(result)) {
			System.out.println("您上传的文件已经存在,请不要重复上传");
			socket.close();
			return;
		}
		// 7.如果不存在, 定义FileInputStream读取文件, 写出到网络
		FileInputStream fis = new FileInputStream(file);
		byte[] arr = new byte[8192];
		int len;
		
		while((len = fis.read(arr)) != -1) {
			ps.write(arr, 0, len);
		}
		
		fis.close();
		socket.close();
	}

	private static File getFile() {
		Scanner sc = new Scanner(System.in);				//创建键盘录入对象
		System.out.println("请输入一个文件路径:");
		
		while(true) {
			String line = sc.nextLine();
			File file = new File(line);
			if(!file.exists()) {
				System.out.println("您录入的文件路径不存在,请重新录入:");
			}else if(file.isDirectory()) {
				System.out.println("您录入的是文件夹路径,请输入一个文件路径:");
			}else {
				return file;
			}
		}
	}
}

UpdateServer.java:

import java.io.BufferedReader;
import java.io.File;
import java.io.FileOutputStream;
import java.io.IOException;
import java.io.InputStream;
import java.io.InputStreamReader;
import java.io.PrintStream;
import java.net.ServerSocket;
import java.net.Socket;

public class UpdateServer {

	/**
	 * @param args
	 * @throws IOException 
	 */
	public static void main(String[] args) throws IOException {
		//3,建立多线程的服务器
		ServerSocket server = new ServerSocket(6666);
		System.out.println("服务器启动,绑定6666端口号");
		
		//4.读取文件名
		while(true) {
			final Socket socket = server.accept();					//接受请求
			new Thread() {
				public void run() {
					try {
						InputStream is = socket.getInputStream();
						BufferedReader br = new BufferedReader(new InputStreamReader(is));
						PrintStream ps = new PrintStream(socket.getOutputStream());
						String fileName = br.readLine();
						
						//5.判断文件是否存在, 将结果发回客户端
						File dir = new File("update");
						dir.mkdir();								//创建文件夹
						File file = new File(dir,fileName);			//封装成File对象
						
						if(file.exists()) {							//如果服务器已经存在这个文件
							ps.println("存在");						//将存在写给客户端
							socket.close();							//关闭socket
							return;
						}else {
							ps.println("不存在");
						}
						
						//8.定义FileOutputStream, 从网络读取数据, 存储到本地
						FileOutputStream fos = new FileOutputStream(file);
						byte[] arr = new byte[8192];
						int len;
						while((len = is.read(arr)) != -1) {
							fos.write(arr, 0, len);
						}
						fos.close();
						socket.close();
					} catch (IOException e) {
						e.printStackTrace();
					}
				}
			}.start();
		}
	}
}