package com.main;
import java.io.DataInputStream;
import java.io.File;
import java.io.FileOutputStream;
import java.math.RoundingMode;
import java.net.ServerSocket;
import java.net.Socket;
import java.text.DecimalFormat;
 
/**
 * Îļþ´«ÊäServer¶Ë<br>
 * ¹¦ÄÜ˵Ã÷£º
 *
 * @author ³ÐÇΰ
 * @Date 2019Äê02ÔÂ14ÈÕ
 * @version 1.0
 */
public class FileTransferServer extends ServerSocket {
 
    private static final int SERVER_PORT = 10100; // ·þÎñ¶Ë¶Ë¿Ú
 
    private static DecimalFormat df = null;
 
    static {
        // ÉèÖÃÊý×Ö¸ñʽ£¬±£ÁôһλÓÐЧСÊý
        df = new DecimalFormat("#0.0");
        df.setRoundingMode(RoundingMode.HALF_UP);
        df.setMinimumFractionDigits(1);
        df.setMaximumFractionDigits(1);
    }
 
    public FileTransferServer() throws Exception {
        super(SERVER_PORT);
    }
 
    /**
     * ʹÓÃÏ̴߳¦Àíÿ¸ö¿Í»§¶Ë´«ÊäµÄÎļþ
     * @throws Exception
     */
    public void load() throws Exception {
        while (true) {
            // server³¢ÊÔ½ÓÊÕÆäËûSocketµÄÁ¬½ÓÇëÇó£¬serverµÄaccept·½·¨ÊÇ×èÈûʽµÄ
            Socket socket = this.accept();
            /**
             * ÎÒÃǵķþÎñ¶Ë´¦Àí¿Í»§¶ËµÄÁ¬½ÓÇëÇóÊÇͬ²½½øÐеģ¬ ÿ´Î½ÓÊÕµ½À´×Ô¿Í»§¶ËµÄÁ¬½ÓÇëÇóºó£¬
             * ¶¼ÒªÏȸúµ±Ç°µÄ¿Í»§¶ËͨÐÅÍêÖ®ºó²ÅÄÜÔÙ´¦ÀíÏÂÒ»¸öÁ¬½ÓÇëÇó¡£ ÕâÔÚ²¢·¢±È½Ï¶àµÄÇé¿öÏ»áÑÏÖØÓ°Ïì³ÌÐòµÄÐÔÄÜ£¬
             * Ϊ´Ë£¬ÎÒÃÇ¿ÉÒÔ°ÑËü¸ÄΪÈçÏÂÕâÖÖÒì²½´¦ÀíÓë¿Í»§¶ËͨÐŵķ½Ê½
             */
            // ÿ½ÓÊÕµ½Ò»¸öSocket¾Í½¨Á¢Ò»¸öеÄÏß³ÌÀ´´¦ÀíËü
            new Thread(new Task(socket)).start();
        }
    }
 
    /**
     * ´¦Àí¿Í»§¶Ë´«Êä¹ýÀ´µÄÎļþÏß³ÌÀà
     */
    class Task implements Runnable {
 
        private Socket socket;
 
        private DataInputStream dis;
 
        private FileOutputStream fos;
 
        public Task(Socket socket) {
            this.socket = socket;
        }
 
        @Override
        public void run() {
            try {
                dis = new DataInputStream(socket.getInputStream());
 
                // ÎļþÃûºÍ³¤¶È
                String fileName = dis.readUTF();
                long fileLength = dis.readLong();
                
                System.out.println(fileName+"====="+fileLength);
                File directory = new File("D:\\FTCache");
                if(!directory.exists()) {
                    directory.mkdir();
                }
                File file = new File(directory.getAbsolutePath() + File.separatorChar + fileName);
                fos = new FileOutputStream(file);
 
                // ¿ªÊ¼½ÓÊÕÎļþ
                byte[] bytes = new byte[1024];
                int length = 0;
                while((length = dis.read(bytes, 0, bytes.length)) != -1) {
                    fos.write(bytes, 0, length);
                    fos.flush();
                }
                System.out.println("======== Îļþ½ÓÊճɹ¦ [File Name£º" + fileName + "] [Size£º" + getFormatFileSize(fileLength) + "] ========");
            } catch (Exception e) {
                e.printStackTrace();
            } finally {
                try {
                    if(fos != null)
                        fos.close();
                    if(dis != null)
                        dis.close();
                    socket.close();
                } catch (Exception e) {}
            }
        }
    }
 
    /**
     * ¸ñʽ»¯Îļþ´óС
     * @param length
     * @return
     */
    private String getFormatFileSize(long length) {
        double size = ((double) length) / (1 << 30);
        if(size >= 1) {
            return df.format(size) + "GB";
        }
        size = ((double) length) / (1 << 20);
        if(size >= 1) {
            return df.format(size) + "MB";
        }
        size = ((double) length) / (1 << 10);
        if(size >= 1) {
            return df.format(size) + "KB";
        }
        return length + "B";
    }
 
    /**
     * Èë¿Ú
     * @param args
     */
    public static void main(String[] args) {
        try {
            FileTransferServer server = new FileTransferServer(); // Æô¶¯·þÎñ¶Ë
            server.load();
        } catch (Exception e) {
            e.printStackTrace();
        }
    }
}