### Question:
ObjectCache { public void invalidateAll() { sharedCache.get().invalidateAll(keyPrefix); } ObjectCache(Supplier<SharedCache> cache, CacheIdentifier prefix); boolean contains(ObjectId id); void invalidateAll(); void invalidate(ObjectId id); void put(RevObject obj); @Nullable RevObject getIfPresent(ObjectId id);  }### Answer:
public @Test void testInvalidateAll() { cache1.invalidateAll(); verify(mockSharedCache, times(1)).invalidateAll(eq(cacheId1)); }