javax.persistence.spi.ProviderUtil Maven / Gradle / Ivy
/*******************************************************************************
* 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.spi;
/**
* Utility interface implemented by the persistence provider. This
* interface is invoked by the {@link
* javax.persistence.PersistenceUtil} implementation to determine
* the load status of an entity or entity attribute.
*
* @since Java Persistence 2.0
*/
public interface ProviderUtil {
/**
* If the provider determines that the entity has been provided
* by itself and that the state of the specified attribute has
* been loaded, this method returns LoadState.LOADED.
* If the provider determines that the entity has been provided
* by itself and that either entity attributes with FetchType.EAGER
* have not been loaded or that the state of the specified
* attribute has not been loaded, this methods returns
* LoadState.NOT_LOADED.
*
If a provider cannot determine the load state, this method
* returns LoadState.UNKNOWN.
*
The provider's implementation of this method must not obtain
* a reference to an attribute value, as this could trigger the
* loading of entity state if the entity has been provided by a
* different provider.
* @param entity entity instance
* @param attributeName name of attribute whose load status is
* to be determined
* @return load status of the attribute
*/
public LoadState isLoadedWithoutReference(Object entity, String attributeName);
/**
* If the provider determines that the entity has been provided
* by itself and that the state of the specified attribute has
* been loaded, this method returns LoadState.LOADED.
*
If a provider determines that the entity has been provided
* by itself and that either the entity attributes with FetchType.EAGER
* have not been loaded or that the state of the specified
* attribute has not been loaded, this method returns
* return LoadState.NOT_LOADED.
*
If the provider cannot determine the load state, this method
* returns LoadState.UNKNOWN.
*
The provider's implementation of this method is permitted to
* obtain a reference to the attribute value. (This access is
* safe because providers which might trigger the loading of the
* attribute state will have already been determined by
* isLoadedWithoutReference. )
*
* @param entity entity instance
* @param attributeName name of attribute whose load status is
* to be determined
* @return load status of the attribute
*/
public LoadState isLoadedWithReference(Object entity, String attributeName);
/**
* If the provider determines that the entity has been provided
* by itself and that the state of all attributes for which
* FetchType.EAGER has been specified have been loaded, this
* method returns LoadState.LOADED.
*
If the provider determines that the entity has been provided
* by itself and that not all attributes with FetchType.EAGER
* have been loaded, this method returns LoadState.NOT_LOADED.
*
If the provider cannot determine if the entity has been
* provided by itself, this method returns LoadState.UNKNOWN.
*
The provider's implementation of this method must not obtain
* a reference to any attribute value, as this could trigger the
* loading of entity state if the entity has been provided by a
* different provider.
* @param entity whose loaded status is to be determined
* @return load status of the entity
*/
public LoadState isLoaded(Object entity);
}