The PetDAO class is used for various database operations on the Pet entity.

Finish the findNamedPetsBySpecies method so that it returns all pets of the appropriate species. The method should not return any Pets whose name field is null. The method accepts a Hibernate Session object that it should use to make the query.

For example, if the Pets table contains:

id  name   species
--------------------
0   Lady   Dog
1   Max    Cat
2   null   Camel

calling findNamedPetsBySpecies with "Cat" as the species, should return a list that contains a pet named "Max" with the id 1.