import java.io.FileInputStream;
import java.io.FileOutputStream;
import java.nio.channels.FileChannel;
public class Main {
public static void main(String[] args) throws Exception {
String fromFileName = "from.txt";
String toFileName = "to.txt";
FileChannel in = new FileInputStream(fromFileName).getChannel();
FileChannel out = new FileOutputStream(toFileName).getChannel();
in.transferTo(0, (int) in.size(), out);
in.close();
out.close();
}
}