Is there a sophisticated file system monitor for Java which is freeware or open source? [closed]

Answer 1

If you are comfortable working on the bleeding edge of Java, have a look at JSR 203: More New I/O APIs aka nio2 which is due out in Java 7.

A new filesystem interface that supports bulk access to file attributes, change notification, escape to filesystem-specific APIs, and a service-provider interface for pluggable filesystem implementations;