Trying to take this method and optimize performance:
public T getByPrimaryKey(PK id) {
T entity = getEntityManager().find(getEntityClass(), id);
if(entity != null) {
preProcessEntity(entity);
}
fireEvent(entity, IEntityEventService.Event.READ, null);
return entity;
}
The reason is that we have many areas where we get a list of Ids based on native queries, and they are getting processed individually, leading to single queries created by Hibernate. I want to have Hibernate fetch these all at once.
public List<T> getEntitiesByPrimaryKey(List<PK> pks) {
CriteriaBuilder cb = getEntityManager().getCriteriaBuilder();
CriteriaQuery<T> cq = cb.createQuery(getEntityClass());
Root<T> root = cq.from(getEntityClass());
Metamodel m = getEntityManager().getMetamodel();
EntityType<T> T_ = m.entity(getEntityClass());
Path<T> keyPath = root.get(T_.getDeclaredId(getEntityClass()));
cq.select(root);
cq.where(keyPath.in(pks));
List<T> entities = getEntityManager().createQuery(cq).getResultList();
if(entities != null) {
for (T entity : entities) {
preProcessEntity(entity);
fireEvent(entity, IEntityEventService.Event.READ, null);
}
}
return entities;
}
I don't know where to go from here. Primary keys are not guaranteed to be Integer but almost certainly will be.
Here's what fixed it: