ImmutableReducingState extends ImmutableState implements ReducingState<V> { @Override public void clear() { throw MODIFICATION_ATTEMPT_ERROR; } private  ImmutableReducingState(V value); @Override V get(); @Override void add(V newValue); @Override void clear(); static ImmutableReducingState<V> createState(
			final ReducingStateDescriptor<V> stateDescriptor,
			final byte[] serializedState);  }
@Test(expected = UnsupportedOperationException.class) public void testClear() { long value = reduceState.get(); assertEquals(42L, value); reduceState.clear(); }