About EntityManager

81-90 of 200Refresh
Manual
13

JPA Lifecycle Events

(added to the EntityManager). @PostPersist - after storing a new entity in the database (during commit or ... - when an entity is identified as modified by the EntityManager. @PostUpdate - after updating an entity in ... the EntityManager. @PostRemove - after deleting an entity from the database (during commit or flush). An entity
Tutorial
13

Step 3: Define an EJB Session Bean

; import java.util.List; import javax.ejb.Stateless; import javax.persistence.EntityManager; import ... class GuestDao { // Injected database connection: @PersistenceContext private EntityManager ... ). Prepares an EntityManager automatically and injects it into the em field (because it is annotated
Manual
13

Query Parameters in JPA [2011-04-01]

getCountryByName(EntityManager em, String name) { TypedQuery query = em.createQuery ... : public Country getCountryByName(EntityManager em, String name) { TypedQuery query = em ... without parameters: public Country getCountryByName(EntityManager em, String name
Manual
13

Query Parameters in JPA

getCountryByName(EntityManager em, String name) { TypedQuery query = em.createQuery ... : public Country getCountryByName(EntityManager em, String name) { TypedQuery query = em ... without parameters: public Country getCountryByName(EntityManager em, String name
Result
11

ObjectDB Object Database Features

and timeout. Caching L1 entity object cache (per EntityManager). L2 shared entity data cache ... on an EntityManager/PersistenceManager. Supports automatic download of created backups from the server
Manual
11

SELECT clause (JPQL / Criteria API)

The ability to retrieve managed entity objects is a major advantage of JPQL. For example, the following query returns Country objects that become managed by the EntityManager em: TypedQuery ... are not associated with an EntityManager and changes to them when a transaction is active are not
Tutorial
11

Step 4: Add a Servlet Class

)getServletContext().getAttribute("emf"); EntityManager em = emf.createEntityManager ... , and then an EntityManager (representing a database connection) is constructed. If a new guest
Manual
11

Entity Management Settings

the persistence context of the EntityManager (which serves as a first level cache). The valid values are "weak ... all its EntityManager instances. The level 2 cache is disabled by specifying 0 or 0mb. The element
Manual
11

JPA Metamodel API

by the EntityManager's getMetamodel method (both methods are equivalent). For example, given an EntityManager, em, a Metamodel instance can be obtained by: Metamodel metamodel = em.getMetamodel
Tutorial
11

Step 4: Add a Servlet Class

"); EntityManager em = emf.createEntityManager(); try { // Handle a new guest (if any ... is retrieved from the application scope attribute, and then an EntityManager (representing a database