This is a spinoff of http://issues.apache.org/jira/browse/LUCENE-305.
I've opened this new issue to capture that it's wider scope than
This is a patch originally created by Jeff Patterson (see above link)
and then modified as described here:
with some small additional changes:
- For each FSDirectory.getDirectory(), I made a corresponding
version that also accepts a LockFactory instance. So, you can
construct an FSDirectory with your own LockFactory.
- Cascaded defaulting for FSDirectory's LockFactory implementation:
if you pass in a LockFactory instance, it's used; else if
setDisableLocks was called, we use NoLockFactory; else, if the
system property "org.apache.lucene.store.FSDirectoryLockFactoryClass"
is defined, we use that; finally, we'll use the original locking
The gist is that all locking code has been moved out of *Directory and
into subclasses of a new abstract LockFactory class. You can now set
the LockFactory of a Directory to change how it does locking. For
example, you can create an FSDirectory but set its locking to
SingleInstanceLockFactory (if you know all writing/reading will take
place a single JVM).
The changes pass all unit tests (on Ubuntu Linux Sun Java 1.5 and
Windows XP Sun Java 1.4), and I added another TestCase to test the
Note that LockFactory defaults are not changed: FSDirectory defaults
to SimpleFSLockFactory and RAMDirectory defaults to
Next step (separate issue) is to create a LockFactory that uses the OS
native locks (through java.nio).