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javafiledetectfile-watcher

Detect a file that will be modified


I have a large directory containing files that are modified by a seperate system at varying intervals. I am running a watcher on this directory to detect which files are modified.

I'm wondering if there is some sort of trigger that occurs when a file is accessed by the system for modification. If so, the following would apply:

Using Java, is it possible to detect which files are about to be modified and make a temporary backup before that happens?
Alternately, is it possible to compare the newly modified file against it's previous version?

In this scenario, it is impossible to make a back up of every file as the files are large and there are many of them.

Example:

I have four files:

a.xml
b.xml
c.xml
d.log

b.xml has a new section added.

Is it possible to copy the newly created section into d.log?


Solution

  • No. you can not detect a file that will be modified. not until they come up with a highly accurate future predicting AI system.

    your best approach would be to maintain a versioned backup of the the files. I would start with looking into some source code management system design considerations.