Search Hibernate Entities By Prototype

I've got JPA entity class like this: @Entity @Table(name = 'person') public class Person { @Id private Long id; private String lastName; private String firstName; pr

Solution 1:

So you're looking for a prototype? Hibernate has a handy Example criteria just for this, so if you don't mind tying yourself to the Hibernate API, try this example from the docs:

Cat cat = new Cat();
cat.setSex('F');
cat.setColor(Color.BLACK);
List results = session.createCriteria(Cat.class)
    .add( Example.create(cat) )
    .list();

It specifically says:

Version properties, identifiers and associations are ignored. By default, null valued properties are excluded.

Which is just what you appear to want.

Solution 2:

You should look into Hibernate Criteria. You can stack restrictions as such:

List cats = sess.createCriteria(Cat.class)
    .add( Restrictions.like("name", "Fritz%") )
    .add( Restrictions.or(
        Restrictions.eq( "age", new Integer(0) ),
        Restrictions.isNull("age")
    ) )
    .list();

Restrictions refer to annotated variables in the class. Take a look at the documentation.