How to avoid hardcoded field names in HQL, Hibernate?

Question

Suppose that I have the following HQL:

String hql = "select e.aField from MyEntity as e";

If I want to refactor and change the name of the MyEntity's member variable aField to something else, I also have to change all occurrences in the whole code in Strings. If I forget to change one hql string the code breaks.

How can I avoid this from happening?

Answer 1

you cannot since they are only strings (hard to refactoring by definition)

Answer 2

Use an IDE that's smart enough to know how to do it for you, like IntelliJ. If I rename a class or variable, IntelliJ finds every use and manages the change for me.

Answer 3

You can used NamedQueries - you put your HQL as value of annotation on any entity and they are compiled to SQL at start-up time. if you have any errors in hql you wont be able to start your WebApp.

Answer 4

Options: 1. Use Criteria instead of HQL 2. Use NHibernateToLinq 3. create an enum of all of your attributes for each class and use that in you HQL (concatenation required)