Locking Copier : FileChannel « File « Java Tutorial

1. Java Tutorial
2. File
3. FileChannel

import java.io.FileInputStream;
import java.io.FileOutputStream;
import java.io.IOException;
import java.nio.channels.FileChannel;
import java.nio.channels.FileLock;

public class MainClass {

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

    FileInputStream inFile = new FileInputStream(args[0]);
    FileOutputStream outFile = new FileOutputStream(args[1]);

    FileChannel inChannel = inFile.getChannel();
    FileChannel outChannel = outFile.getChannel();

    FileLock outLock = outChannel.lock();
    FileLock inLock = inChannel.lock(0, inChannel.size(), true);

    inChannel.transferTo(0, inChannel.size(), outChannel);

    outLock.release();
    inLock.release();

    inChannel.close();
    outChannel.close();
  }
}