When tarring up files which are already all in the right location, we can use <tarfileset filemode="755"> to make certain parts executable.

    <tar destfile="${tar.name}" compression="bzip2">
        <tarfileset dir="${dir}" filemode="755">
            <patternset refid="executable-files"/>
        </tarfileset>
        <tarfileset dir="${dir}" >
            <patternset refid="non-executable-files"/>
        </tarfileset>
    </tar>

However, having to copy all the files into one location just to tar them again adds noticeable build time (the tar file is about 200 MB) so in cases where executable flags don't matter, we do something like this:

    <union id="included.files.common">
        <fileset dir="${our.jars.dir}" includes="*.jar"/>
    </union>
    <union id="included.files.app">
        <fileset dir="src/app-base" includes="bin/*"/>
    </union>

    <tar destfile="${tar.name}" compression="bzip2">
        <mappedresources>
            <union>
                <resources refid="included.files.common"/>
                <resources refid="included.files.app"/>
            </union>
            <globmapper from="*" to="${base-name}-${product.fullversion}/*"/>
        </mappedresources>
    </tar>

I would like to be able to combine the two approaches, so that I can keep the reuse and copy-avoiding benefits of using resource collections but also keep the ability top put specific permissions on the files.

One way to do this would be to add the filemode attribute to <fileset/>, something like this:

    <union id="included.files.common">
        <fileset dir="${our.jars.dir}" includes="*.jar" filemode="755"/>
    </union>

The implementation would go something like this:

   1. Move getMode() from ArchiveResource up to Resource.
   2. Implement getMode() in any subclasses like FileResource. Some other
      subclasses might also make sense to add this information to.
   3. In any tasks casting to ArchiveResource, weaken the cast.

Then any file modes at the lower levels of the resource collections would just propagate upwards and automatically work.