Java tutorial
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 { String fromFileName = "from.txt"; String toFileName = "to.txt"; FileChannel in = new FileInputStream(fromFileName).getChannel(); FileChannel out = new FileOutputStream(toFileName).getChannel(); ByteBuffer buff = ByteBuffer.allocateDirect(32 * 1024); while (in.read(buff) > 0) { buff.flip(); out.write(buff); buff.clear(); } in.close(); out.close(); } }