/**
* Tries to run garbage collection, and waits for the {@link WeakReference}s to the {@link Thing}s
* in the maps last returned by {@link Parent#things()} and {@link Child#things()} for {@code
* keys} to be cleared.
*/
void gcAndWaitUntilWeakReferencesCleared(final Class<?>... keys) {
GcFinalization.awaitDone(
new FinalizationPredicate() {
@Override
public boolean isDone() {
for (Class<?> key : keys) {
if (parentAsserts.weakThingReferenceUncollected(key)
|| childAsserts.weakThingReferenceUncollected(key)) {
return false;
}
}
return true;
}
});
}
public void testProxyClassUnloading() {
Object testObject =
Guice.createInjector(interceptorModule, testModule).getInstance(proxyTestClass);
assertNotNull(testObject.getClass().getClassLoader());
assertNotSame(testObject.getClass().getClassLoader(), systemClassLoader);
// take a weak reference to the generated proxy class
WeakReference<Class<?>> clazzRef = new WeakReference<Class<?>>(testObject.getClass());
assertNotNull(clazzRef.get());
// null the proxy
testObject = null;
/*
* this should be enough to queue the weak reference
* unless something is holding onto it accidentally.
*/
GcFinalization.awaitClear(clazzRef);
// This test could be somewhat flaky when the GC isn't working.
// If it fails, run the test again to make sure it's failing reliably.
assertNull("Proxy class was not unloaded.", clazzRef.get());
}