import java.io.*;
import java.nio.*;
import java.nio.channels.*;
import java.net.*;
class DupFile {

    void copyThruChannel(String fname) throws Exception {
        File f = new File(fname);
        FileInputStream fin = new FileInputStream(f);
        int len = (int) f.length();

        FileChannel fc = fin.getChannel();
        System.out.println("allocating buff");
        ByteBuffer myBB = ByteBuffer.allocate(len);
        int bytesRead = fc.read(myBB);
        myBB.flip();

        System.out.println("getting fout channel");
        FileOutputStream fos = new FileOutputStream(fname+".copy");
        FileChannel fco = fos.getChannel();
        int bytesWritten = fco.write(myBB);
        fco.close();
    }

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

        DupFile client = new DupFile();
        client.copyThruChannel(a[0]);
    }
}