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/*******************************************************************************
* Copyright (c) 2008 - 2013 Oracle Corporation. All rights reserved.
*
* This program and the accompanying materials are made available under the
* terms of the Eclipse Public License v1.0 and Eclipse Distribution License v. 1.0
* which accompanies this distribution.
* The Eclipse Public License is available at http://www.eclipse.org/legal/epl-v10.html
* and the Eclipse Distribution License is available at
* http://www.eclipse.org/org/documents/edl-v10.php.
*
* Contributors:
* Linda DeMichiel - Java Persistence 2.1
* Linda DeMichiel - Java Persistence 2.0
*
******************************************************************************/
package javax.persistence;
import java.util.Map;
import java.util.List;
import javax.persistence.metamodel.Metamodel;
import javax.persistence.criteria.CriteriaBuilder;
import javax.persistence.criteria.CriteriaQuery;
import javax.persistence.criteria.CriteriaUpdate;
import javax.persistence.criteria.CriteriaDelete;
/**
* Interface used to interact with the persistence context.
*
* An EntityManager instance is associated with
* a persistence context. A persistence context is a set of entity
* instances in which for any persistent entity identity there is
* a unique entity instance. Within the persistence context, the
* entity instances and their lifecycle are managed.
* The EntityManager API is used
* to create and remove persistent entity instances, to find entities
* by their primary key, and to query over entities.
*
*
The set of entities that can be managed by a given
* EntityManager instance is defined by a persistence
* unit. A persistence unit defines the set of all classes that are
* related or grouped by the application, and which must be
* colocated in their mapping to a single database.
*
* @see Query
* @see TypedQuery
* @see CriteriaQuery
* @see PersistenceContext
* @see StoredProcedureQuery
*
* @since Java Persistence 1.0
*/
public interface EntityManager {
/**
* Make an instance managed and persistent.
* @param entity entity instance
* @throws EntityExistsException if the entity already exists.
* (If the entity already exists, the EntityExistsException may
* be thrown when the persist operation is invoked, or the
* EntityExistsException or another PersistenceException may be
* thrown at flush or commit time.)
* @throws IllegalArgumentException if the instance is not an
* entity
* @throws TransactionRequiredException if there is no transaction when
* invoked on a container-managed entity manager of that is of type
* PersistenceContextType.TRANSACTION
*/
public void persist(Object entity);
/**
* Merge the state of the given entity into the
* current persistence context.
* @param entity entity instance
* @return the managed instance that the state was merged to
* @throws IllegalArgumentException if instance is not an
* entity or is a removed entity
* @throws TransactionRequiredException if there is no transaction when
* invoked on a container-managed entity manager of that is of type
* PersistenceContextType.TRANSACTION
*/
public T merge(T entity);
/**
* Remove the entity instance.
* @param entity entity instance
* @throws IllegalArgumentException if the instance is not an
* entity or is a detached entity
* @throws TransactionRequiredException if invoked on a
* container-managed entity manager of type
* PersistenceContextType.TRANSACTION and there is
* no transaction
*/
public void remove(Object entity);
/**
* Find by primary key.
* Search for an entity of the specified class and primary key.
* If the entity instance is contained in the persistence context,
* it is returned from there.
* @param entityClass entity class
* @param primaryKey primary key
* @return the found entity instance or null if the entity does
* not exist
* @throws IllegalArgumentException if the first argument does
* not denote an entity type or the second argument is
* is not a valid type for that entity's primary key or
* is null
*/
public T find(Class entityClass, Object primaryKey);
/**
* Find by primary key, using the specified properties.
* Search for an entity of the specified class and primary key.
* If the entity instance is contained in the persistence
* context, it is returned from there.
* If a vendor-specific property or hint is not recognized,
* it is silently ignored.
* @param entityClass entity class
* @param primaryKey primary key
* @param properties standard and vendor-specific properties
* and hints
* @return the found entity instance or null if the entity does
* not exist
* @throws IllegalArgumentException if the first argument does
* not denote an entity type or the second argument is
* is not a valid type for that entity's primary key or
* is null
* @since Java Persistence 2.0
*/
public T find(Class entityClass, Object primaryKey,
Map properties);
/**
* Find by primary key and lock.
* Search for an entity of the specified class and primary key
* and lock it with respect to the specified lock type.
* If the entity instance is contained in the persistence context,
* it is returned from there, and the effect of this method is
* the same as if the lock method had been called on the entity.
* If the entity is found within the persistence context and the
* lock mode type is pessimistic and the entity has a version
* attribute, the persistence provider must perform optimistic
* version checks when obtaining the database lock. If these
* checks fail, the OptimisticLockException will be thrown.
*
If the lock mode type is pessimistic and the entity instance
* is found but cannot be locked:
*
* - the
PessimisticLockException will be thrown if the database
* locking failure causes transaction-level rollback
* - the
LockTimeoutException will be thrown if the database
* locking failure causes only statement-level rollback
*
* @param entityClass entity class
* @param primaryKey primary key
* @param lockMode lock mode
* @return the found entity instance or null if the entity does
* not exist
* @throws IllegalArgumentException if the first argument does
* not denote an entity type or the second argument is
* not a valid type for that entity's primary key or
* is null
* @throws TransactionRequiredException if there is no
* transaction and a lock mode other than NONE is
* specified or if invoked on an entity manager which has
* not been joined to the current transaction and a lock
* mode other than NONE is specified
* @throws OptimisticLockException if the optimistic version
* check fails
* @throws PessimisticLockException if pessimistic locking
* fails and the transaction is rolled back
* @throws LockTimeoutException if pessimistic locking fails and
* only the statement is rolled back
* @throws PersistenceException if an unsupported lock call
* is made
* @since Java Persistence 2.0
*/
public T find(Class entityClass, Object primaryKey,
LockModeType lockMode);
/**
* Find by primary key and lock, using the specified properties.
* Search for an entity of the specified class and primary key
* and lock it with respect to the specified lock type.
* If the entity instance is contained in the persistence context,
* it is returned from there.
* If the entity is found
* within the persistence context and the lock mode type
* is pessimistic and the entity has a version attribute, the
* persistence provider must perform optimistic version checks
* when obtaining the database lock. If these checks fail,
* the OptimisticLockException will be thrown.
*
If the lock mode type is pessimistic and the entity instance
* is found but cannot be locked:
*
* - the
PessimisticLockException will be thrown if the database
* locking failure causes transaction-level rollback
* - the
LockTimeoutException will be thrown if the database
* locking failure causes only statement-level rollback
*
* If a vendor-specific property or hint is not recognized,
* it is silently ignored.
*
Portable applications should not rely on the standard timeout
* hint. Depending on the database in use and the locking
* mechanisms used by the provider, the hint may or may not
* be observed.
* @param entityClass entity class
* @param primaryKey primary key
* @param lockMode lock mode
* @param properties standard and vendor-specific properties
* and hints
* @return the found entity instance or null if the entity does
* not exist
* @throws IllegalArgumentException if the first argument does
* not denote an entity type or the second argument is
* not a valid type for that entity's primary key or
* is null
* @throws TransactionRequiredException if there is no
* transaction and a lock mode other than NONE is
* specified or if invoked on an entity manager which has
* not been joined to the current transaction and a lock
* mode other than NONE is specified
* @throws OptimisticLockException if the optimistic version
* check fails
* @throws PessimisticLockException if pessimistic locking
* fails and the transaction is rolled back
* @throws LockTimeoutException if pessimistic locking fails and
* only the statement is rolled back
* @throws PersistenceException if an unsupported lock call
* is made
* @since Java Persistence 2.0
*/
public T find(Class entityClass, Object primaryKey,
LockModeType lockMode,
Map properties);
/**
* Get an instance, whose state may be lazily fetched.
* If the requested instance does not exist in the database,
* the EntityNotFoundException is thrown when the instance
* state is first accessed. (The persistence provider runtime is
* permitted to throw the EntityNotFoundException when
* getReference is called.)
* The application should not expect that the instance state will
* be available upon detachment, unless it was accessed by the
* application while the entity manager was open.
* @param entityClass entity class
* @param primaryKey primary key
* @return the found entity instance
* @throws IllegalArgumentException if the first argument does
* not denote an entity type or the second argument is
* not a valid type for that entity's primary key or
* is null
* @throws EntityNotFoundException if the entity state
* cannot be accessed
*/
public T getReference(Class entityClass,
Object primaryKey);
/**
* Synchronize the persistence context to the
* underlying database.
* @throws TransactionRequiredException if there is
* no transaction or if the entity manager has not been
* joined to the current transaction
* @throws PersistenceException if the flush fails
*/
public void flush();
/**
* Set the flush mode that applies to all objects contained
* in the persistence context.
* @param flushMode flush mode
*/
public void setFlushMode(FlushModeType flushMode);
/**
* Get the flush mode that applies to all objects contained
* in the persistence context.
* @return flushMode
*/
public FlushModeType getFlushMode();
/**
* Lock an entity instance that is contained in the persistence
* context with the specified lock mode type.
* If a pessimistic lock mode type is specified and the entity
* contains a version attribute, the persistence provider must
* also perform optimistic version checks when obtaining the
* database lock. If these checks fail, the
* OptimisticLockException will be thrown.
*
If the lock mode type is pessimistic and the entity instance
* is found but cannot be locked:
*
* - the
PessimisticLockException will be thrown if the database
* locking failure causes transaction-level rollback
* - the
LockTimeoutException will be thrown if the database
* locking failure causes only statement-level rollback
*
* @param entity entity instance
* @param lockMode lock mode
* @throws IllegalArgumentException if the instance is not an
* entity or is a detached entity
* @throws TransactionRequiredException if there is no
* transaction or if invoked on an entity manager which
* has not been joined to the current transaction
* @throws EntityNotFoundException if the entity does not exist
* in the database when pessimistic locking is
* performed
* @throws OptimisticLockException if the optimistic version
* check fails
* @throws PessimisticLockException if pessimistic locking fails
* and the transaction is rolled back
* @throws LockTimeoutException if pessimistic locking fails and
* only the statement is rolled back
* @throws PersistenceException if an unsupported lock call
* is made
*/
public void lock(Object entity, LockModeType lockMode);
/**
* Lock an entity instance that is contained in the persistence
* context with the specified lock mode type and with specified
* properties.
* If a pessimistic lock mode type is specified and the entity
* contains a version attribute, the persistence provider must
* also perform optimistic version checks when obtaining the
* database lock. If these checks fail, the
* OptimisticLockException will be thrown.
*
If the lock mode type is pessimistic and the entity instance
* is found but cannot be locked:
*
* - the
PessimisticLockException will be thrown if the database
* locking failure causes transaction-level rollback
* - the
LockTimeoutException will be thrown if the database
* locking failure causes only statement-level rollback
*
* If a vendor-specific property or hint is not recognized,
* it is silently ignored.
*
Portable applications should not rely on the standard timeout
* hint. Depending on the database in use and the locking
* mechanisms used by the provider, the hint may or may not
* be observed.
* @param entity entity instance
* @param lockMode lock mode
* @param properties standard and vendor-specific properties
* and hints
* @throws IllegalArgumentException if the instance is not an
* entity or is a detached entity
* @throws TransactionRequiredException if there is no
* transaction or if invoked on an entity manager which
* has not been joined to the current transaction
* @throws EntityNotFoundException if the entity does not exist
* in the database when pessimistic locking is
* performed
* @throws OptimisticLockException if the optimistic version
* check fails
* @throws PessimisticLockException if pessimistic locking fails
* and the transaction is rolled back
* @throws LockTimeoutException if pessimistic locking fails and
* only the statement is rolled back
* @throws PersistenceException if an unsupported lock call
* is made
* @since Java Persistence 2.0
*/
public void lock(Object entity, LockModeType lockMode,
Map properties);
/**
* Refresh the state of the instance from the database,
* overwriting changes made to the entity, if any.
* @param entity entity instance
* @throws IllegalArgumentException if the instance is not
* an entity or the entity is not managed
* @throws TransactionRequiredException if there is no
* transaction when invoked on a container-managed
* entity manager of type PersistenceContextType.TRANSACTION
* @throws EntityNotFoundException if the entity no longer
* exists in the database
*/
public void refresh(Object entity);
/**
* Refresh the state of the instance from the database, using
* the specified properties, and overwriting changes made to
* the entity, if any.
* If a vendor-specific property or hint is not recognized,
* it is silently ignored.
* @param entity entity instance
* @param properties standard and vendor-specific properties
* and hints
* @throws IllegalArgumentException if the instance is not
* an entity or the entity is not managed
* @throws TransactionRequiredException if there is no
* transaction when invoked on a container-managed
* entity manager of type PersistenceContextType.TRANSACTION
* @throws EntityNotFoundException if the entity no longer
* exists in the database
* @since Java Persistence 2.0
*/
public void refresh(Object entity,
Map properties);
/**
* Refresh the state of the instance from the database,
* overwriting changes made to the entity, if any, and
* lock it with respect to given lock mode type.
* If the lock mode type is pessimistic and the entity instance
* is found but cannot be locked:
*
* - the
PessimisticLockException will be thrown if the database
* locking failure causes transaction-level rollback
* - the
LockTimeoutException will be thrown if the
* database locking failure causes only statement-level
* rollback.
*
* @param entity entity instance
* @param lockMode lock mode
* @throws IllegalArgumentException if the instance is not
* an entity or the entity is not managed
* @throws TransactionRequiredException if invoked on a
* container-managed entity manager of type
* PersistenceContextType.TRANSACTION when there is
* no transaction; if invoked on an extended entity manager when
* there is no transaction and a lock mode other than NONE
* has been specified; or if invoked on an extended entity manager
* that has not been joined to the current transaction and a
* lock mode other than NONE has been specified
* @throws EntityNotFoundException if the entity no longer exists
* in the database
* @throws PessimisticLockException if pessimistic locking fails
* and the transaction is rolled back
* @throws LockTimeoutException if pessimistic locking fails and
* only the statement is rolled back
* @throws PersistenceException if an unsupported lock call
* is made
* @since Java Persistence 2.0
*/
public void refresh(Object entity, LockModeType lockMode);
/**
* Refresh the state of the instance from the database,
* overwriting changes made to the entity, if any, and
* lock it with respect to given lock mode type and with
* specified properties.
* If the lock mode type is pessimistic and the entity instance
* is found but cannot be locked:
*
* - the
PessimisticLockException will be thrown if the database
* locking failure causes transaction-level rollback
* - the
LockTimeoutException will be thrown if the database
* locking failure causes only statement-level rollback
*
* If a vendor-specific property or hint is not recognized,
* it is silently ignored.
*
Portable applications should not rely on the standard timeout
* hint. Depending on the database in use and the locking
* mechanisms used by the provider, the hint may or may not
* be observed.
* @param entity entity instance
* @param lockMode lock mode
* @param properties standard and vendor-specific properties
* and hints
* @throws IllegalArgumentException if the instance is not
* an entity or the entity is not managed
* @throws TransactionRequiredException if invoked on a
* container-managed entity manager of type
* PersistenceContextType.TRANSACTION when there is
* no transaction; if invoked on an extended entity manager when
* there is no transaction and a lock mode other than NONE
* has been specified; or if invoked on an extended entity manager
* that has not been joined to the current transaction and a
* lock mode other than NONE has been specified
* @throws EntityNotFoundException if the entity no longer exists
* in the database
* @throws PessimisticLockException if pessimistic locking fails
* and the transaction is rolled back
* @throws LockTimeoutException if pessimistic locking fails and
* only the statement is rolled back
* @throws PersistenceException if an unsupported lock call
* is made
* @since Java Persistence 2.0
*/
public void refresh(Object entity, LockModeType lockMode,
Map properties);
/**
* Clear the persistence context, causing all managed
* entities to become detached. Changes made to entities that
* have not been flushed to the database will not be
* persisted.
*/
public void clear();
/**
* Remove the given entity from the persistence context, causing
* a managed entity to become detached. Unflushed changes made
* to the entity if any (including removal of the entity),
* will not be synchronized to the database. Entities which
* previously referenced the detached entity will continue to
* reference it.
* @param entity entity instance
* @throws IllegalArgumentException if the instance is not an
* entity
* @since Java Persistence 2.0
*/
public void detach(Object entity);
/**
* Check if the instance is a managed entity instance belonging
* to the current persistence context.
* @param entity entity instance
* @return boolean indicating if entity is in persistence context
* @throws IllegalArgumentException if not an entity
*/
public boolean contains(Object entity);
/**
* Get the current lock mode for the entity instance.
* @param entity entity instance
* @return lock mode
* @throws TransactionRequiredException if there is no
* transaction or if the entity manager has not been
* joined to the current transaction
* @throws IllegalArgumentException if the instance is not a
* managed entity and a transaction is active
* @since Java Persistence 2.0
*/
public LockModeType getLockMode(Object entity);
/**
* Set an entity manager property or hint.
* If a vendor-specific property or hint is not recognized, it is
* silently ignored.
* @param propertyName name of property or hint
* @param value value for property or hint
* @throws IllegalArgumentException if the second argument is
* not valid for the implementation
* @since Java Persistence 2.0
*/
public void setProperty(String propertyName, Object value);
/**
* Get the properties and hints and associated values that are in effect
* for the entity manager. Changing the contents of the map does
* not change the configuration in effect.
* @return map of properties and hints in effect for entity manager
* @since Java Persistence 2.0
*/
public Map getProperties();
/**
* Create an instance of Query for executing a
* Java Persistence query language statement.
* @param qlString a Java Persistence query string
* @return the new query instance
* @throws IllegalArgumentException if the query string is
* found to be invalid
*/
public Query createQuery(String qlString);
/**
* Create an instance of TypedQuery for executing a
* criteria query.
* @param criteriaQuery a criteria query object
* @return the new query instance
* @throws IllegalArgumentException if the criteria query is
* found to be invalid
* @since Java Persistence 2.0
*/
public TypedQuery createQuery(CriteriaQuery criteriaQuery);
/**
* Create an instance of Query for executing a criteria
* update query.
* @param updateQuery a criteria update query object
* @return the new query instance
* @throws IllegalArgumentException if the update query is
* found to be invalid
* @since Java Persistence 2.1
*/
public Query createQuery(CriteriaUpdate updateQuery);
/**
* Create an instance of Query for executing a criteria
* delete query.
* @param deleteQuery a criteria delete query object
* @return the new query instance
* @throws IllegalArgumentException if the delete query is
* found to be invalid
* @since Java Persistence 2.1
*/
public Query createQuery(CriteriaDelete deleteQuery);
/**
* Create an instance of TypedQuery for executing a
* Java Persistence query language statement.
* The select list of the query must contain only a single
* item, which must be assignable to the type specified by
* the resultClass argument.
* @param qlString a Java Persistence query string
* @param resultClass the type of the query result
* @return the new query instance
* @throws IllegalArgumentException if the query string is found
* to be invalid or if the query result is found to
* not be assignable to the specified type
* @since Java Persistence 2.0
*/
public TypedQuery createQuery(String qlString, Class resultClass);
/**
* Create an instance of Query for executing a named query
* (in the Java Persistence query language or in native SQL).
* @param name the name of a query defined in metadata
* @return the new query instance
* @throws IllegalArgumentException if a query has not been
* defined with the given name or if the query string is
* found to be invalid
*/
public Query createNamedQuery(String name);
/**
* Create an instance of TypedQuery for executing a
* Java Persistence query language named query.
* The select list of the query must contain only a single
* item, which must be assignable to the type specified by
* the resultClass argument.
* @param name the name of a query defined in metadata
* @param resultClass the type of the query result
* @return the new query instance
* @throws IllegalArgumentException if a query has not been
* defined with the given name or if the query string is
* found to be invalid or if the query result is found to
* not be assignable to the specified type
* @since Java Persistence 2.0
*/
public TypedQuery createNamedQuery(String name, Class resultClass);
/**
* Create an instance of Query for executing
* a native SQL statement, e.g., for update or delete.
* If the query is not an update or delete query, query
* execution will result in each row of the SQL result
* being returned as a result of type Object[] (or a result
* of type Object if there is only one column in the select
* list.) Column values are returned in the order of their
* appearance in the select list and default JDBC type
* mappings are applied.
* @param sqlString a native SQL query string
* @return the new query instance
*/
public Query createNativeQuery(String sqlString);
/**
* Create an instance of Query for executing
* a native SQL query.
* @param sqlString a native SQL query string
* @param resultClass the class of the resulting instance(s)
* @return the new query instance
*/
public Query createNativeQuery(String sqlString, Class resultClass);
/**
* Create an instance of Query for executing
* a native SQL query.
* @param sqlString a native SQL query string
* @param resultSetMapping the name of the result set mapping
* @return the new query instance
*/
public Query createNativeQuery(String sqlString, String resultSetMapping);
/**
* Create an instance of StoredProcedureQuery for executing a
* stored procedure in the database.
* Parameters must be registered before the stored procedure can
* be executed.
*
If the stored procedure returns one or more result sets,
* any result set will be returned as a list of type Object[].
* @param name name assigned to the stored procedure query
* in metadata
* @return the new stored procedure query instance
* @throws IllegalArgumentException if a query has not been
* defined with the given name
* @since Java Persistence 2.1
*/
public StoredProcedureQuery createNamedStoredProcedureQuery(String name);
/**
* Create an instance of StoredProcedureQuery for executing a
* stored procedure in the database.
*
Parameters must be registered before the stored procedure can
* be executed.
*
If the stored procedure returns one or more result sets,
* any result set will be returned as a list of type Object[].
* @param procedureName name of the stored procedure in the
* database
* @return the new stored procedure query instance
* @throws IllegalArgumentException if a stored procedure of the
* given name does not exist (or the query execution will
* fail)
* @since Java Persistence 2.1
*/
public StoredProcedureQuery createStoredProcedureQuery(String procedureName);
/**
* Create an instance of StoredProcedureQuery for executing a
* stored procedure in the database.
*
Parameters must be registered before the stored procedure can
* be executed.
*
The resultClass arguments must be specified in the order in
* which the result sets will be returned by the stored procedure
* invocation.
* @param procedureName name of the stored procedure in the
* database
* @param resultClasses classes to which the result sets
* produced by the stored procedure are to
* be mapped
* @return the new stored procedure query instance
* @throws IllegalArgumentException if a stored procedure of the
* given name does not exist (or the query execution will
* fail)
* @since Java Persistence 2.1
*/
public StoredProcedureQuery createStoredProcedureQuery(
String procedureName, Class... resultClasses);
/**
* Create an instance of StoredProcedureQuery for executing a
* stored procedure in the database.
*
Parameters must be registered before the stored procedure can
* be executed.
*
The resultSetMapping arguments must be specified in the order
* in which the result sets will be returned by the stored
* procedure invocation.
* @param procedureName name of the stored procedure in the
* database
* @param resultSetMappings the names of the result set mappings
* to be used in mapping result sets
* returned by the stored procedure
* @return the new stored procedure query instance
* @throws IllegalArgumentException if a stored procedure or
* result set mapping of the given name does not exist
* (or the query execution will fail)
*/
public StoredProcedureQuery createStoredProcedureQuery(
String procedureName, String... resultSetMappings);
/**
* Indicate to the entity manager that a JTA transaction is
* active and join the persistence context to it.
*
This method should be called on a JTA application
* managed entity manager that was created outside the scope
* of the active transaction or on an entity manager of type
* SynchronizationType.UNSYNCHRONIZED to associate
* it with the current JTA transaction.
* @throws TransactionRequiredException if there is
* no transaction
*/
public void joinTransaction();
/**
* Determine whether the entity manager is joined to the
* current transaction. Returns false if the entity manager
* is not joined to the current transaction or if no
* transaction is active
* @return boolean
* @since Java Persistence 2.1
*/
public boolean isJoinedToTransaction();
/**
* Return an object of the specified type to allow access to the
* provider-specific API. If the provider's EntityManager
* implementation does not support the specified class, the
* PersistenceException is thrown.
* @param cls the class of the object to be returned. This is
* normally either the underlying EntityManager implementation
* class or an interface that it implements.
* @return an instance of the specified class
* @throws PersistenceException if the provider does not
* support the call
* @since Java Persistence 2.0
*/
public T unwrap(Class cls);
/**
* Return the underlying provider object for the EntityManager,
* if available. The result of this method is implementation
* specific.
* The unwrap method is to be preferred for new applications.
* @return underlying provider object for EntityManager
*/
public Object getDelegate();
/**
* Close an application-managed entity manager.
* After the close method has been invoked, all methods
* on the EntityManager instance and any
* Query, TypedQuery, and
* StoredProcedureQuery objects obtained from
* it will throw the IllegalStateException
* except for getProperties,
* getTransaction, and isOpen (which will return false).
* If this method is called when the entity manager is
* joined to an active transaction, the persistence
* context remains managed until the transaction completes.
* @throws IllegalStateException if the entity manager
* is container-managed
*/
public void close();
/**
* Determine whether the entity manager is open.
* @return true until the entity manager has been closed
*/
public boolean isOpen();
/**
* 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
*/
public EntityTransaction getTransaction();
/**
* Return the entity manager factory for the entity manager.
* @return EntityManagerFactory instance
* @throws IllegalStateException if the entity manager has
* been closed
* @since Java Persistence 2.0
*/
public EntityManagerFactory getEntityManagerFactory();
/**
* Return an instance of CriteriaBuilder for the creation of
* CriteriaQuery objects.
* @return CriteriaBuilder instance
* @throws IllegalStateException if the entity manager has
* been closed
* @since Java Persistence 2.0
*/
public CriteriaBuilder getCriteriaBuilder();
/**
* 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 Java Persistence 2.0
*/
public Metamodel getMetamodel();
/**
* Return a mutable EntityGraph that can be used to dynamically create an
* EntityGraph.
* @param rootType class of entity graph
* @return entity graph
* @since Java Persistence 2.1
*/
public EntityGraph createEntityGraph(Class rootType);
/**
* Return a mutable copy of the named EntityGraph. If there
* is no entity graph with the specified name, null is returned.
* @param graphName name of an entity graph
* @return entity graph
* @since Java Persistence 2.1
*/
public EntityGraph createEntityGraph(String graphName);
/**
* Return a named EntityGraph. The returned EntityGraph
* should be considered immutable.
* @param graphName name of an existing entity graph
* @return named entity graph
* @throws IllegalArgumentException if there is no EntityGraph of
* the given name
* @since Java Persistence 2.1
*/
public EntityGraph getEntityGraph(String graphName);
/**
* Return all named EntityGraphs that have been defined for the provided
* class type.
* @param entityClass entity class
* @return list of all entity graphs defined for the entity
* @throws IllegalArgumentException if the class is not an entity
* @since Java Persistence 2.1
*/
public List> getEntityGraphs(Class entityClass);
}