AlwaysQueryExpression extends BaseQueryExpression { @Override public Pipe asPipe() { return null; } protected  AlwaysQueryExpression(); @Override Pipe asPipe(); @Override boolean evaluate(VertexWrapper vWrapper); @Override boolean evaluate(Object value);  }
@Test public void testAsPipe() { VertexWrapper v = createStrictMock(VertexWrapper.class); replay(v); QueryExpression expression = new AlwaysQueryExpression(); assertNull(expression.asPipe()); verify(v); }