jpa-2.0

Let's say I have a Meeting entity. Each meeting has a single attendee and a meeting date. Within my meeting table I may have multiple meetings for each attendee, with different dates for each. I need a JPA query that will select only the latest meeting for all attendees. For instance, if my table looks like this Meeting ID | Attendee ID | Meeting Date 1 | 1 | 6/1/2011 2 | 2 | 6/1/2011 3 | 1 | 6/6/2011 4 | 3 | 6/6/2011 My result should be Meeting ID | Attendee ID | Meeting Date 2 | 2 | 6/1/2011 3 | 1 | 6/6/2011 4 | 3 | 6/6/2011 Using JPA 2 against postgres. Meeting has 1-1 to attendee and a

Using JPA 2 with EclipseLink implementation. I'm trying to build a dynamic query which should bring me some records persisted after a given date. CriteriaBuilder builder = em.getCriteriaBuilder(); CriteriaQuery<Event> criteria = builder.createQuery(Event.class); Root<Event> root = criteria.from(Event.class); criteria.select(root); criteria.distinct(true); List<Predicate> predicates = new ArrayList<Predicate>(); //... if (dateLimit != null){ ParameterExpression<Date> param = builder.parameter(Date.class, "dateLimit"); predicates.add(builder.lessThanOrEqualTo(root.get("dateCreated"), param)); }

Since the programmer is forced to catch all checked exception, I to throw checked exception in case of any problem. I would like to rollback on any of those expections. Writing rollbackFor=Exception.class on every @Transactional annotation is very error-prone, so I would like to tell spring, that: "whenever I write @Transactional , I mean @Transactional(rollbackFor=Exception.class) ". I know, that I could create a custom annotation, but that seems unnatural. So is there a way to tell spring how it should handle checked excpetions globally ? Custom Shortcut Annotations I know, that I could

I have a following problem with entity mapping in JPA. I have two entities, first one is Lookup and the second is Text which represents translations for entities. Now I need to bound Lookup to the Text but I don't want Text to have reference to Lookup. To make this more complicated, Text does not use its primary key in this relationship but a metacode defined in a TXTHEAD_CODE column. Lookup.java @Entity @Table(name = "DATREG") public class Lookup implements PersistableEntity { @Id @Column(name = "DATREG_META_CODE") private String metaCode; @OneToMany @JoinTable(name="TXT", joinColumns=

Typically , I use Hibernate's @Cache(usage = CacheConcurrencyStrategy.NONSTRICT_READ_WRITE) to cache an @Entity class , and it works well. In JPA2 , there's another @Cacheable annotation that seems to be the same functionality with Hibernate's @Cache. To make my entity class independent of hibernate's package , I want to give it a try. But I cannot make it work. Each time a simple id query still hits the DB. Can anybody tell me where goes wrong ? Thanks. Entity class : @Entity //@Cache(usage = CacheConcurrencyStrategy.NONSTRICT_READ_WRITE) @Cacheable(true) public class User implements

I've been trying to find a JPA Criteria API tutorial but haven't been much successful. Do you know about any for beginners? I'd like to start using it in an Java5/Maven app to build complex search queries. The Dynamic, typesafe queries in JPA 2.0 article is a very good one on this topic, actually the best one I've found so far online , even better than the Chapter 23 Using the Criteria API to Create Queries from the Java EE 6 tutorials (that contains some mistakes). Examples of common queries are here All examples are in this form: CriteriaBuilder cb = em.getCriteriaBuilder(); // Query for a