NiO copy file call getchannel method transferfrom()

package kj15.niuzi.pojo;


import org.junit.Test;

import java.io.*;
import java.nio.channels.FileChannel;

public class Test01  {


    @Test
    public void test01() throws IOException {
        FileInputStream ifo = new FileInputStream(new File("d:/abc"));
        // Get file channel 
        FileChannel channel = ifo.getChannel();
        FileOutputStream fos=new FileOutputStream(new File("d:/bcd"));
        FileChannel channel1 = fos.getChannel();
        // Copy file contents to another file 
        // call transferFrom Method 
        channel1.transferFrom(channel,0,channel.size());

//        byte[] bts=new byte[ifo.available()];   //available() Method to get the size of the file 
        byte[] bts=new byte[1024];
        // Traversal file 
        // Definition len Is the number of bytes read 
        int len=0;
        while(ifo.read(bts)!=-1){
            fos.write(bts);
        }
//
//
//        ifo.read(bts);
//        fos.write(bts);
        fos.close();
        ifo.close();
    }
}