import java.net.*;
import java.io.*;

public class Server {
	// 服务器监听端口
	private int port;
	// 文件保存路径
	private String path;
	// 判断server是否启动
	private boolean started = false;

	public static void main(String[] args) {
		new Server(8888, "E:/").listen(8888);
	}

	// 初始化服务器端口及文件保存路径
	private Server(int port, String path) {
		this.port = port;
		this.path = path;
	}

	// 二进制转换为十进制
	public static int b2i(byte[] b) {
		int value = 0;
		for (int i = 0; i < 4; i++) {
			int shift = (4 - 1 - i) * 8;
			value += (b[i] & 0x000000FF) << shift;
		}
		return value;
	}

	public static long b2l(byte[] b) {
		long s = 0;
		long s0 = b[0] & 0xff;
		long s1 = b[1] & 0xff;
		long s2 = b[2] & 0xff;
		long s3 = b[3] & 0xff;
		long s4 = b[4] & 0xff;
		long s5 = b[5] & 0xff;
		long s6 = b[6] & 0xff;
		long s7 = b[7] & 0xff;
		s1 <<= 8;
		s2 <<= 16;
		s3 <<= 24;
		s4 <<= 8 * 4;
		s5 <<= 8 * 5;
		s6 <<= 8 * 6;
		s7 <<= 8 * 7;
		s = s0 | s1 | s2 | s3 | s4 | s5 | s6 | s7;
		return s;
	}

	// 主线程始终处于监听状态，等待客户端连接
	private void listen(int port) {
		Socket s = null;
		ServerSocket ss = null;
		try {
			ss = new ServerSocket(port);
			started = true;
			System.out.println("监听端口：" + port);
			while (started) {
				s = ss.accept();
				System.out.println("A client connected!");
				new Thread(new HandleThread(s)).start();
			}
		} catch (IOException e) {
			e.printStackTrace();
		}

	}

	// 处理接收文件并做相关处理的线程类
	private class HandleThread implements Runnable {
		Socket s = null;

		private HandleThread(Socket s) {
			this.s = s;
		}

		public void run() {
			String name = getName(s);
			System.out.println(name);
			String isOver = getFile(name, s);
			System.out.println(isOver);
		}

		// 1、先获取文件名，并按照文件名创建相应文件壳，用于储存文件内容
		private String getName(Socket s) {
			try {
				InputStream is = s.getInputStream();
				BufferedInputStream bis = new BufferedInputStream(is);
				byte[] buffer1 = new byte[4];
				bis.read(buffer1);
				int name_len = b2i(buffer1);
				System.out.println("s_name_len = " + name_len);
				// 开始获取文件名
				byte[] buffer2 = new byte[name_len];
				bis.read(buffer2);
				return new String(buffer2);
			} catch (IOException e) {
				return new String("接收过程出现故障！");
			}

		}

		// 2、开始接收文件
		private String getFile(String name, Socket s) {
			InputStream is = null;
			BufferedInputStream bis = null;
			FileOutputStream fos = null;
			BufferedOutputStream bos = null;
			File file = null;
			try {
				file = new File(path + "/" + name);
				if (!file.exists()) {
					file.createNewFile();
				}
				is = s.getInputStream();
				bis = new BufferedInputStream(is);
				fos = new FileOutputStream(file);
				bos = new BufferedOutputStream(fos);
				byte[] bytes = new byte[8];
				bis.read(bytes);
				long size = b2l(bytes);
				System.out.println("s_size = " + size);
				byte[] buffer = new byte[1024];
				long count = 0;
				while (count < size) {
					long num = bis.read(buffer);
					
					bos.write(buffer);
					count = count + num;
				}
				/*
				int a = -1;
				while ((a = bis.read()) != -1) {
					bos.write(a);
				}*/
				bos.flush();
				bos.close();
				return "文件 " + file.getName() + " 大小  " + file.length()
						+ "接收完成！";

			} catch (IOException e) {
				return "接收失败";
			} finally {
				try {
					if (bos != null) {
						bos.close();
						bos = null;
					}
					if (fos != null) {
						fos.close();
						fos = null;
					}
					if (bis != null) {
						bis.close();
						bis = null;
					}
					if (is != null) {
						is.close();
						is = null;
					}
					if (s != null) {
						s.close();
						s = null;
					}
				} catch (IOException e) {
					e.printStackTrace();
				}
			}
		}
	}
}

import java.net.*;
import java.io.*;

public class Client {
	// 服务器ip地址
	private String ipAdd;
	// 服务器监听端口号
	private int port;
	// 发送文件路径
	private String path;

	public static void main(String[] args) {
		new Client("127.0.0.1", 8888, "D:\\把悲伤留给自己.mp3").connect();
	}

	public Client(String ipAdd, int port, String path) {
		this.ipAdd = ipAdd;
		this.port = port;
		this.path = path;
	}

	// 连接到服务器
	private void connect() {
		Socket s = null;
		OutputStream os = null;
		BufferedOutputStream bos = null;
		try {
			s = new Socket(ipAdd, port);
			os = s.getOutputStream();
			bos = new BufferedOutputStream(os);
			File file = new File(path);
			// 文件名
			String name = file.getName();
			// 文件大小
			long size = file.length();
			System.out.printf("%s%s%s%s%s", "Sending file ", name, " size ",
					size, " bytes to server...");
			// 先发送文件名到服务器
			boolean completed1 = sendName(name, bos);
			boolean completed2 = sendContent(file, bos);
			if (completed1 && completed2) {
				System.out.println("文件发送成功");
			} else {
				System.out.println("文件发送失败");
			}
		} catch (UnknownHostException e) {
			e.printStackTrace();
		} catch (IOException e) {
			System.out.println("文件未检测到");
		} finally {
			try {
				if (bos != null) {
					bos.close();
					bos = null;
				}
				if (os != null) {
					os.close();
					os = null;
				}
			} catch (IOException e) {

			}
		}

	}

	// 整型数据转换为byte数据方法
	public static byte[] i2b(int i) {
		return new byte[] { (byte) ((i >> 24) & 0xFF),
				(byte) ((i >> 16) & 0xFF), (byte) ((i >> 8) & 0xFF),
				(byte) (i & 0xFF) };
	}

	// long类型转成byte数组

	public static byte[] l2b(long number) {
		long temp = number;
		byte[] b = new byte[8];
		for (int i = 0; i < b.length; i++) {
			b[i] = new Long(temp & 0xff).byteValue();
			temp = temp >> 8; // 向右移8位
		}
		return b;
	}

	// 发送文件名长度以及文件名到服务器
	private boolean sendName(String name, BufferedOutputStream bos) {
		byte[] buffer = name.getBytes();
		int name_len = buffer.length;
		try {
			// 这就要求文件名长度不能长于65535，当然，这显然不太可能！！！
			bos.write(i2b(name_len));
			bos.write(buffer);
			bos.flush();
			return true;
		} catch (IOException e) {
			return false;
		}

	}

	// 发送文件内容到服务器
	private boolean sendContent(File file, BufferedOutputStream bos) {
		try {
			long size = file.length();
			// 先发送文件长度
			bos.write(l2b(size));
			FileInputStream fis = new FileInputStream(file);
			BufferedInputStream bis = new BufferedInputStream(fis);
			byte[] buffer = new byte[1024];
			long count = 0;
			// 一边读入，一边写出
			while (count < size) {
				long d = bis.read(buffer);
				count = count + d;
				bos.write(buffer);
			}
			bos.flush();
			return true;
		} catch (FileNotFoundException e) {
			System.out.println("未检测到发送文件！");
			return false;
		} catch (IOException e) {
			return false;
		}
	}
}