BundleURLScanner

When?

You should use the BundleURLScanner if you wish to implement an extender that is triggered by existence of specific files or directories in bundles.

Examples

Pax Web Extender - War

Pax Web Extender - War uses Pax Swissbox - Extender / BundleURLScanner to trigger web applications registration / unregistration as soon as a WAR bundle gets started or stopped. You can browse the code (hhttps://scm.ops4j.org/repos/ops4j/projects/pax/web-extender/war/src/main/java/org/ops4j/pax/web/extender/war/internal/Activator.java) as a real life example.

WAR extender

The following is an example of how you can implement an extender bundle for war files:


new BundleWatcher<URL>(
    bundleContext,
    new BundleURLScanner(
        "WEB-INF/",
        "web.xml",
        false // do not recurse
    ),
    new BundleObserver<URL>()
    {
        public void addingEntries( Bundle bundle, List<URL> entries )
        {
            // process web xml, as for example parsing and registering servlets
        }

        public void removingEntries( Bundle bundle, List<URL> entries )
        {
            // revert processing of web xml
        }
    }
).start();