休眠条件：dto作为实体

Question

I have a query built with Hibernate Criteria (I show you only the "main" part):

Criteria criteria = sessionProvider.get().createCriteria(User.class);
// Add other stuff to the query like joins, group-bys, order-bys etc.
// In the projection list add the "id" of the user.
projectionList.add(Projections.property("id"), "id");
// finally using same entity class User as dto
criteria.setResultTransformer(Transformers.aliasToBean(User.class));

so I can finally do:

List<User> users = criteria.list();

Problem comes when I try to load values from this entities. For example:

users.get(0).getFirstName();

returns null. So basically the entities created like "dtos" by Transformers.aliasToBean which have received only the "id" by projection are not working as normal entities loaded by get/load/etc.

Is there any way to make these dto "working" as entities?

Answer 1

Seems passing argument in projectionList is wrong, you need to modify the projectionList like this.

Criteria criteria = sessionProvider.get().createCriteria(User.class);
//Add other stuff to the query like joins, group-bys, order-bys etc.

//In the projection list add the columns name which are mapped with the entity
ProjectionList projectionList = Projections.projectionList();
projectionList.add(Projections.property("id"));
projectionList.add(Projections.property("firstName"));
criteria.setProjection(projectionList);

List<User> results = criteria.list();

//output results
for(User user : results) {
    user.getFirstName();        
}