javax.persistence.EntityManager Maven / Gradle / Ivy
// $Id: EntityManager.java 17752 2009-10-15 01:19:21Z [email protected] $
// EJB3 Specification Copyright 2004-2009 Sun Microsystems, Inc.
package javax.persistence;
import java.util.Map;
import javax.persistence.metamodel.Metamodel;
import javax.persistence.criteria.CriteriaBuilder;
import javax.persistence.criteria.CriteriaQuery;
/**
* 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
*
* @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 invoked on a
* container-managed entity manager of type
* PersistenceContextType.TRANSACTION and there is
* no 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 invoked on a
* container-managed entity manager of type
* PersistenceContextType.TRANSACTION and there is
* no 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 entitys 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 entitys 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
* @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
* @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 entitys 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
* @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
* @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
* @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 invoked on a
* container-managed entity manager of type
* PersistenceContextType.TRANSACTION and there is
* no 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 invoked on a
* container-managed entity manager of type
* PersistenceContextType.TRANSACTION and there is
* no 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 there is no
* transaction and if invoked on a container-managed
* EntityManager instance with
* PersistenceContextType.TRANSACTION or with a lock mode
* other than NONE
* @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 there is no
* transaction and if invoked on a container-managed
* EntityManager instance with
* PersistenceContextType.TRANSACTION or with a lock mode
* other than NONE
* @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
* @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 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.
* @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);
/**
* Indicate to the entity manager that a JTA transaction is
* active. This method should be called on a JTA application
* managed entity manager that was created outside the scope
* of the active transaction to associate it with the current
* JTA transaction.
* @throws TransactionRequiredException if there is
* no transaction
*/
public void joinTransaction();
/**
* 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 and TypedQuery
* 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
* associated with 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();
}