Existing solution for file deltas/versioning in Java

Question

When versioning or optimizing file backups one idea is to use only the delta or data that has been modified.

This sounds like a simple idea at first but actually determining where unmodified data ends and new data starts comes accross as a difficult task.

Is there an existing framework that already does something like this or an efficient file comparison algorithm?

Answer 1

XDelta is not Java but is worth looking at anyway. There is Java version of it but I don't know how stable is it.