Should I have a lock on a file when I want to delete it?

I have a bunch of files on a local file system. My server will serve those files. In some cases the server will receive an instruction to delete a file. At the moment I'm using FileChannel.lock() to acquire a lock on the file, this is mostly to make sure that some other process isn't editing the file when I try to delete it.
If I successfully acquire the lock, can I delete the file straight away, or do I need to release the lock first?
like this:

FileOutputStream out = new FileOutputStream(file);
FileChannel channel = out.getChannel();
FileLock lock = channel.lock();
if(lock.isValid() && !lock.isShared()){
    Path filePath = Paths.get(file.getPath());
    Files.delete(filePath);
}

Do I need to release the lock after I've deleted the file?

Or should it be like this (lock.release() added):

FileOutputStream out = new FileOutputStream(file);
FileChannel channel = out.getChannel();
FileLock lock = channel.lock();
if(lock.isValid() && !lock.isShared()){
    lock.release();
    Path filePath = Paths.get(file.getPath());
    Files.delete(filePath);
}

EDIT:
So it turns out the code above wouldn't work anyway, because you can't modify the file with a FileInputStream because, of course, it's read only. I've modified the code above to use FileOutputStream instead, but it still doesn't quite work, because even though I release the lock from the channel, the file object still has a lock. So I modified the code like so:

FileOutputStream out = new FileOutputStream(file);
                    FileChannel channel = out.getChannel();
                    FileLock lock = channel.lock();
                    if(lock.isValid() && !lock.isShared()){
                        channel.close();
                        boolean deleted = file.delete();
                        logger.info("{} @{} File {} deleted: {}", id, type, file.getName(), deleted);
                    }

This seems to work as expected. I'd still like to know if this is safe, or if there's a better way to do this?

File lock wont work while deleting the file. File lock will work only while some other process wants to edit the same file. Before deleting the file , you need to release the lock and close the channel