About getReference


Retrieving JPA Entity Objects

Explains how to use JPA to retrieve entity objects from the database.... null is returned. A similar method, getReference getReference(entityClass, primaryKey) EntityManager's method Get an ... version of find : Employee employee = em. getReference getReference(entityClass, primaryKey) EntityManager's ...


getReference(entityClass, primaryKey)

Get an instance, whose state may be lazily fetched.(Method of javax.persistence.EntityManager)


Persist error @ManyToMany how to define correct entities relationships

I have Product entities containing a list of Category enties. Each product can have multiple Category but all sue the same limited set of Category entities. There is not changes made to Category from Product. The category ID is taken from the webservice Object ID (unique too). ... to existing Category instances (possibly using em.getReference getReference(entityClass, primaryKey) EntityManager's method Get an ...



Interface used to interact with the persistence context.(Interface of JPA)


Searching lists within objects

Hi everyone,  I've a problem with searching on lists. I'm uncertain as to what the best form is, so I've created a maven project with all the classes and a unit test showing my issue. Pretty much I want to search using cb.isMember passing an object. This however does NOT work. I'm uncertain how the database is doing its matching, but it looks to me like it matches using objectids, which means you can only match isMember if you have a database object. This does not help as I'm never going to have the real object at search time. ... use: Attribute attributeLastName = em. getReference ( Attribute . class , williamLastNameAttribute. ...