### Question:
AncestorChildExpansionIterator implements SortedKeyValueIterator<Key,Value> { @Override public Value getTopValue() { if (!seeked) { throw new IllegalStateException("cannot getTopKey(), iterator has not been seeked"); } if (topValue == null) { throw new NoSuchElementException("top value does not exist"); } return topValue; } AncestorChildExpansionIterator(SortedKeyValueIterator<Key,Value> iterator, List<String> children, Equality equality); @Override void init(SortedKeyValueIterator<Key,Value> source, Map<String,String> options, IteratorEnvironment env); @Override boolean hasTop(); @Override void next(); @Override void seek(Range range, Collection<ByteSequence> columnFamilies, boolean inclusive); @Override Key getTopKey(); @Override Value getTopValue(); @Override SortedKeyValueIterator<Key,Value> deepCopy(IteratorEnvironment env);  }### Answer:
@Test(expected = IllegalStateException.class) public void testUninitializedgetTopValue() { iterator.getTopValue(); }