ant : jar and zipfileset - copy files from one JAR into another

Question

I am currently doing this:

    <jar update="yes"
      jarfile="${pwd}/dist/${release}_installer.jar">
      <zipfileset src="${pwd}/dist/app.jar" includes="com/izforge/izpack/panels/**"/>
      <zipfileset src="${pwd}/dist/app.jar" includes="com/xyz/img/logo.png"/>
    </jar>

My existing installer JAR gets updated to include the files as needed, extracted from the app JAR.

So far, so good.

However, I want to modify the behaviour such that the path of the image file is different than what is being copied from:

Currently:

com/izforge/izpack/panels/MyIzPanel.class
com/xyz/img/logo.png

What I want:

com/izforge/izpack/panels/MyIzPanel.class
blah/img/logo.png

So I need to copy the files, but use <zipfileset> and <jar> in such a way that I can modify the directory structure.

Is there a way to do this, apart from unzipping the entire contents copying file and then zipping it back up again?

---

EDIT:

Link to earlier related question: http://stackoverflow.com/questions/2521231/ant-task-to-remove-files-from-a-jar

Answer 1

You can use the fullpath attribute:

<zipfileset src="${pwd}/dist/app.jar"
    includes="com/xyz/img/logo.png" fullpath="blah/img/logo.img"/>

If you need to copy several files you may want to have a look at the prefix attribute, e.g.:

<zipfileset src="${pwd}/dist/app.jar"
    includes="**/*.png" prefix="blah/img"/>