How to get classloader for a bundle in equinox?

Question

I have read a lot of equinox code for this, but still can't figure out a non-hacky way of getting the classloader for a osgi bundle in eclipse equinox setup. Is there one?

Answer 1

The short answer (certainly for OSGi 4.1, not sure of 4.2) is you can't get a bundle's classloader. However the Bundle interface exposes a loadClass() method and this would allow you to write a classloader that wraps the bundle API and delegates to that loadClass() method. Or you can save some time and use Spring DM's BundleDelegatingClassLoader class instead.

Answer 2

In OSGi 4.3 you can use:

bundle.adapt(BundleWiring.class).getClassLoader()

Answer 3

The class loader of a bundle can be obtained through the BundleWiring interface. Here a short example:

Bundle bundle = bundleContext.getBundle();
BundleWiring bundleWiring = bundle.adapt(BundleWiring.class);
ClassLoader classLoader = bundleWiring.getClassLoader();

Answer 4

In normal java code, you can get the class loader that loaded a given object with

object.getClass().getClassLoader();

Or even just

SomeType.class.getClassLoader();

The same applies to Equinox, just use an object or type that comes from the bundle you are interested in.