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Hi, in the following code you can see an example with EntityManager .refresh(). The example ... -------------------- package example; import java.io.File; import javax.persistence. EntityManager ; import ... ;  public void refreshTest() {         EntityManager

EntityManager with the same unitName. TradesC method needs an User, which is taken from UserDataB ... .pingushare.entity.p1.User#2' belongs to another EntityManager at com.objectdb.o.MSG.d(MSG.java:61 ... this should be a problem if, in the same transaction, an entity is passed into more EntityManagers , but here are 2

an internal pool of connections, and when an EntityManager is closed the underlying socket to the server is returned to the pool and can be reused with another new  EntityManager , as ... ; EntityManager holds is not preserved or reused. Is may be worth reusing these caches as well in some

Hi, I have an issue with the EntityManager . My persistance XML looks like: com.objectdb.jpa.Provider Now in our project we use spring to start everything. If I do: System.out.println(" EntityManager ... , I get: com.objectdb.jdo.PMImpl Whats going on here? Is the entityManager not controlled by

. com.objectdb.o.UserException - Attempt to execute a query using a closed EntityManager at com ... to execute a query using a closed EntityManager at org.apache.myfaces.view.facelets.el ... .o._PersistenceException: Attempt to execute a query using a closed EntityManager at org.apache.el

' belongs to another EntityManager (error 613) 10:29:14,887 ERROR [stderr] (http--10.23.3.98-8081-5 ... to another EntityManager 10:29:15,072 ERROR [stderr] (http--10.23.3.98-8081-5) at com.objectdb.o ... 'pbdmodel.impl.OrgJedinicaImpl#8' belongs to another EntityManager 10:29:15,089 ERROR [stderr] (http--10.23

wherein the EntityManagerFactory objects are being locked during EntityManager object creation.  Please refer ... with ObjectDB wherein the EntityManagerFactory objects are being locked during EntityManager object creation.  This is the normal behavior of ObjectDB. Creation operations of  EntityManager

. EntityManager ; import javax.persistence.TypedQuery; /** * @author Stanislav Jakuschev 28.02.2023 * * EntityManager .find(entityClass, primaryKey) is slow when accessing * non-existent IDs. * * Select queries ... "XId [a=" + a + ", b=" + b + ", c=" + c + "]"; } } public static void clear( EntityManager em) { Instant

Our application manages the Entities itself, so we close the EntityManager after every creating ... and finalize, we found the problem is caused by bad state of EntityManager . After first throwing the InternalException, the EntityManager throws every time when doing merge operation, but it can be closed

with orphanRemoval set to true. I use a new EntityManager for each transaction (which normally happens in ... entity, the database contains 3 child entities. If I use the same EntityManager for both transactions ... ;      EntityManager em = emf.createEntityManager();     

an EntityManagerFactory and later  EntityManager on this file, every thing is working fine ... EntityManager . Do you have any idea why does it crash? Thanks, Marcin  marcins Marcin ObjectDB uses ... .  But still the code crashes while creating  EntityManager on this odb file. And the program

from Metamodel of a differente EntityManager initialized on a @Controller @RequestMapping event. I ... is it: If I have two moments of initialization of "javax.persistence.metamodel" from EntityManager and these two metamodels come from different EntityManagers . One of these is on a @PostConstruct event

JPA Method in javax.persistence. EntityManager EntityTransaction getTransaction () Return the resource-level EntityTransaction object. The EntityTransaction instance may be used serially to begin and commit multiple transactions. Return: EntityTransaction instance Throws: IllegalStateException - if invoked on a JTA entity manager Since: JPA 1.0

JPA Method in javax.persistence. EntityManager EntityManagerFactory getEntityManagerFactory () Return the entity manager factory for the entity manager. Return: EntityManagerFactory instance Throws: IllegalStateException - if the entity manager has been closed Since: JPA 2.0

JPA Method in javax.persistence. EntityManager CriteriaBuilder getCriteriaBuilder () Return an instance of CriteriaBuilder for the creation of CriteriaQuery objects. Return: CriteriaBuilder instance Throws: IllegalStateException - if the entity manager has been closed Since: JPA 2.0

JPA Method in javax.persistence. EntityManager Metamodel getMetamodel () Return an instance of Metamodel interface for access to the metamodel of the persistence unit. Return: Metamodel instance Throws: IllegalStateException - if the entity manager has been closed Since: JPA 2.0

JPA Method in javax.persistence. EntityManager EntityGraph createEntityGraph (   Class  rootType ) Return a mutable EntityGraph that can be used to dynamically create an EntityGraph. Parameters: rootType - class of entity graph Return: entity graph Since: JPA 2.1

JPA Method in javax.persistence. EntityManager EntityGraph createEntityGraph (   String graphName ) Return a mutable copy of the named EntityGraph. If there is no entity graph with the specified name, null is returned. Parameters: graphName - name of an entity graph Return: entity graph Since: JPA 2.1

JPA Method in javax.persistence. EntityManager EntityGraph getEntityGraph (   String graphName ) Return a named EntityGraph. The returned EntityGraph should be considered immutable. Parameters: graphName - name of an existing entity graph Return: named entity graph Throws

JPA Method in javax.persistence. EntityManager List getEntityGraphs (   Class  entityClass ) Return all named EntityGraphs that have been defined for the provided class type. Parameters: entityClass - entity class Return: list of all entity graphs defined for the entity Throws: IllegalArgumentException - if the class is not an entity Since: JPA 2.1

JPA Method in javax.persistence. EntityManager Query createQuery (    CriteriaUpdate  updateQuery ) Create an instance of Query for executing a criteria update query. Parameters: updateQuery - a criteria update query object Return: the new query instance Throws

JPA Method in javax.persistence. EntityManager Query createQuery (    CriteriaDelete  deleteQuery ) Create an instance of Query for executing a criteria delete query. Parameters: deleteQuery - a criteria delete query object Return: the new query instance Throws

(using another EntityManager ) since it was retrieved by the current updater. Optimistic locking ... another EntityManager instance) currently holds a PESSIMISTIC_WRITE lock on that database object ... . lock (e1, lockMode1); em2. lock (e2, lockMode2); em1 and em2 are two EntityManager instances

the entity objects into an EntityManager . Updating the relevant entity object fields  ... and then updating them, but it should be used cautiously because bypassing the EntityManager  may break its synchronization with the database. For example, the EntityManager may not be aware

is invoked: @PrePersist - before a new entity is persisted (added to the EntityManager ... the EntityManager . @PostUpdate - after updating an entity in the database (during commit or flush ). @PreRemove - when an entity is marked for removal in the EntityManager . @PostRemove

getCountryByName( EntityManager em, String name) { TypedQuery query = em. createQuery ( "SELECT c FROM ... ( EntityManager em, String name) { TypedQuery query = em. createQuery ( "SELECT c FROM Country c ... ( EntityManager em, String name) { TypedQuery query = em. createQuery ( "SELECT c FROM Country c

method or 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

is New. An explicit call to persist associates the object with an owner EntityManager em and changes ... managed by the EntityManager ) or by commit . Referenced Embedded Objects The following code stores

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 query ... that are retrieved directly by a result path expression are not associated with an EntityManager and changes

the reference type for holding non dirty entities in the persistence context of the EntityManager ... that is managed by the EntityManagerFactory and shared by all its EntityManager instances. The level 2 cache

(per EntityManager ). L2 shared entity data cache  (per EntityManagerFactory). Database file page cache

entity object from within an active transaction. No EntityManager 's method is invoked to report

with an EntityManager (represented by em in the following code snippets), which serves as a factory

the EntityManagerFactory 's getCriteriaBuilder method or by the  EntityManager 's

Given an EntityManager , em , that represents a JPA connection to the object database, we can use it to store, retrieve, update and delete database objects. Storing New Entity Objects The following code fragment stores 1,000 Point  objects in the database: em. getTransaction (). begin

but different EntityManager factory methods are used to instantiate them. The createNamedQuery method

. Starting Online Backup The online backup can be started by executing a special query on an EntityManager

the EntityManagerFactory 's getCriteriaBuilder method or by the  EntityManager 's getCriteriaBuilder method

; EntityManager em = emf.createEntityManager();         em

  The following exception occures if we call entityManager .flush() where the corresponding JPA PersistenceContext has many entities and relations. What is the reason for the exception? entityManager .getTransaction().commit() instead of a entityManager .flush() works correctly. Unfortunately I

java.util.List; import javax.ejb.Stateless; import javax.persistence. EntityManager ; import javax ... { // Injected database connection: @PersistenceContext private EntityManager em; // Stores a new guest ... ; next step ). Prepares an  EntityManager automatically and injects it into the  em field

. EntityManager ; import javax.persistence.PersistenceContext; import javax.persistence.TypedQuery ... EntityManager em; // Stores a new guest: public void persist(Guest guest) { em.persist(guest ... the next step ). Prepares an EntityManager automatically and injects it into the em field

; import javax.persistence. EntityManager ; import javax.persistence.PersistenceContext; import javax ... connection: @PersistenceContext private EntityManager em; // Stores a new guest: @Transactional public ... the controller, as shown in the next step. Prepares an  EntityManager automatically and injects

.List; import javax.persistence. EntityManager ; import javax.persistence.PersistenceContext; import ... connection: @PersistenceContext private EntityManager em; // Stores a new guest: @Transactional public ... the controller, as shown in the next step. Prepares an  EntityManager automatically and injects

: EntityManagerFactory emf = (EntityManagerFactory)getServletContext().getAttribute("emf"); EntityManager em ... , and then an EntityManager (representing a database connection) is constructed. If a new guest has registered

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

;          "$objectdb/db/p2.odb"); EntityManager em

;        "$objectdb/db/p2.odb"); EntityManager em = emf

, controllers and transactions), to inject a JPA EntityManager , to manage transactions and to look

and transactions), to inject a JPA  EntityManager , to manage transactions and to look for JSP pages in