### Question:
FilteredCacheIterator implements PeekingKeyValueIterator<Bytes, LRUCacheEntry> { @Override public void remove() { throw new UnsupportedOperationException(); } FilteredCacheIterator(final PeekingKeyValueIterator<Bytes, LRUCacheEntry> cacheIterator,
                          final HasNextCondition hasNextCondition,
                          final CacheFunction cacheFunction); @Override void close(); @Override Bytes peekNextKey(); @Override boolean hasNext(); @Override KeyValue<Bytes, LRUCacheEntry> next(); @Override void remove(); @Override KeyValue<Bytes, LRUCacheEntry> peekNext();  }### Answer:
@Test(expected = UnsupportedOperationException.class) public void shouldThrowUnsupportedOperationExeceptionOnRemove() throws Exception { allIterator.remove(); }