URL jarURL = jarFile.toURI().toURL();
ClassLoader loader = new URLClassLoader(new URL[]{jarURL});
Class<?> typeInSignedJar = loader.loadClass("TypeInSignedJar");
assertTrue(imposteriser.canImposterise(typeInSignedJar));
Object o = imposteriser.imposterise(new VoidAction(), typeInSignedJar);
assertTrue(typeInSignedJar.isInstance(o));
}