Java tutorial
/* * Hibernate, Relational Persistence for Idiomatic Java * * License: GNU Lesser General Public License (LGPL), version 2.1 or later. * See the lgpl.txt file in the root directory or <http://www.gnu.org/licenses/lgpl-2.1.html>. */ package org.hibernate; import java.io.Serializable; import java.util.Optional; import org.hibernate.graph.GraphSemantic; import org.hibernate.graph.RootGraph; /** * Loads an entity by its primary identifier. * * @author Eric Dalquist * @author Steve Ebersole */ public interface IdentifierLoadAccess<T> { /** * Specify the {@link LockOptions} to use when retrieving the entity. * * @param lockOptions The lock options to use. * * @return {@code this}, for method chaining */ IdentifierLoadAccess<T> with(LockOptions lockOptions); /** * Specify the {@link CacheMode} to use when retrieving the entity. * * @param cacheMode The CacheMode to use. * * @return {@code this}, for method chaining */ IdentifierLoadAccess<T> with(CacheMode cacheMode); default IdentifierLoadAccess<T> with(RootGraph<T> graph) { return with(graph, GraphSemantic.LOAD); } IdentifierLoadAccess<T> with(RootGraph<T> graph, GraphSemantic semantic); /** * Return the persistent instance with the given identifier, assuming that the instance exists. This method * might return a proxied instance that is initialized on-demand, when a non-identifier method is accessed. * * You should not use this method to determine if an instance exists; to check for existence, use {@link #load} * instead. Use this only to retrieve an instance that you assume exists, where non-existence would be an * actual error. * * @param id The identifier for which to obtain a reference * * @return the persistent instance or proxy */ T getReference(Serializable id); /** * Return the persistent instance with the given identifier, or null if there is no such persistent instance. * If the instance is already associated with the session, return that instance, initializing it if needed. This * method never returns an uninitialized instance. * * @param id The identifier * * @return The persistent instance or {@code null} */ T load(Serializable id); /** * Same semantic as {@link #load} except that here {@link Optional} is returned to * handle nullability. * * @param id The identifier * * @return The persistent instance, if one, wrapped in Optional */ Optional<T> loadOptional(Serializable id); }