package com.test;

 import java.io.FileInputStream;

 import java.io.FileOutputStream;

 import java.nio.ByteBuffer;

 import java.nio.channels.FileChannel;

 public class Main {

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

         FileInputStream fis = new FileInputStream("E://a.txt");

         FileOutputStream fos = new FileOutputStream("E://b.txt");

         FileOutputStream fos2 = new FileOutputStream("E://c.txt");

         FileChannel in = fis.getChannel();

         FileChannel out = fos.getChannel();

         FileChannel out2 = fos2.getChannel();

         ByteBuffer buf = ByteBuffer.allocateDirect(20);

         ByteBuffer buf2 = ByteBuffer.allocateDirect(20);

         while (true) {

             // 从通道in中读数据到buf，然后从buf中读出来写入out通道

             int eof = in.read(buf);

             if (eof == -1)

                 break;

             buf.flip();

             int c = out.write(buf);

             System.out.println("c=" + c);

             buf.clear();

             // 从通道in中读数据到buf，然后从buf中读出来写入out2通道

             int eof2 = in.read(buf2);

             if (eof2 == -1)

                 break;

             buf2.flip();

             int c2 = out2.write(buf2);

             System.out.println("c2=" + c2);

             buf2.clear();

         }

         fis.close();

         fos.close();

         fos2.close();

     }

 }