How to manage a common ant build script across multiple project build jobs on jenkins?

Question

I have a set of java projects coming from different git repositories which I want to be built with Jenkins.

All of them share the same ant build script, which employ

Answer 1

I have also found another option myself:

Declare the "overrideable" part in the common build script as "neutral" element, e.g. for a path definition define an empty path:

Optionally import another build script after the neutral defintion to make it override the existing one:

In the imported file you now can define the element to suit the individual needs of the project to build.