File Concurrency

[Venkat Sidh]

How to handle file concurrency if two different applications (different JVM's) try to edit same file. What is the best way to handle this scenario. Thanks.

[Purushoth Thambu]

Ideally when one file is open in write mode another process should be able to overwrite that file. However the more clean way is to use FileChannel and FileLock classes in java.nio packages. All you have to do is

  FileOutputStream file1 = new FileOutputStream("a.txt");
  java.nio.channels.FileChannel fch = file1.getChannel();
  java.nio.channels.FileLock lock = file1.lock();
  //Process the file
  lock.release();
  fch.close();

lock() is a blocking method. You can use tryLock() version which doesn't block the call.

[Venkat Sidh]

Thanks Purushothaman. Let me try out.