How to find type without using instanceof?

Question

I have a List of interface type Criteria within my class Query.

List criteria = new ArrayList

        

Answer 1

Well, you can...

if (ContextualCriteria.class.equals(c.getClass()) {

... though it's just a fancier-looking way of writing instanceof. (Well, almost: this tests whether it is exactly the class, rather than the class of a subclass -- for that you want isAssignableFrom()).

The right way to get rid of the smell is to implement a polymorphic method in Criteria which is overridden in subclasses, for example.