/*
 * 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;

Loads an entity by its natural identifier.
Author:
Eric Dalquist, Steve Ebersole
See Also:
NaturalId
NaturalIdLoadAccess/**
 * Loads an entity by its natural identifier.
 * 
 * @author Eric Dalquist
 * @author Steve Ebersole
 *
 * @see org.hibernate.annotations.NaturalId
 * @see NaturalIdLoadAccess
 */
public interface SimpleNaturalIdLoadAccess<T> {
	
Specify the LockOptions to use when retrieving the entity. 
Params:
lockOptions – The lock options to use.
Returns:
this, for method chaining/**
	 * Specify the {@link org.hibernate.LockOptions} to use when retrieving the entity.
	 *
	 * @param lockOptions The lock options to use.
	 *
	 * @return {@code this}, for method chaining
	 */
	SimpleNaturalIdLoadAccess<T> with(LockOptions lockOptions);

	
For entities with mutable natural ids, should Hibernate perform "synchronization" prior to performing 
lookups?  The default is to perform "synchronization" (for correctness).
 See NaturalIdLoadAccess.setSynchronizationEnabled for detailed discussion. 
Params:
enabled – Should synchronization be performed? true indicates synchronization will be performed; false indicates it will be circumvented.
Returns:
this, for method chaining/**
	 * For entities with mutable natural ids, should Hibernate perform "synchronization" prior to performing 
	 * lookups?  The default is to perform "synchronization" (for correctness).
	 * <p/>
	 * See {@link NaturalIdLoadAccess#setSynchronizationEnabled} for detailed discussion.
	 *
	 * @param enabled Should synchronization be performed?  {@code true} indicates synchronization will be performed;
	 * {@code false} indicates it will be circumvented.
	 *
	 * @return {@code this}, for method chaining
	 */
	SimpleNaturalIdLoadAccess<T> setSynchronizationEnabled(boolean enabled);

	
Return the persistent instance with the given natural id value, 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 load instead. Use this only to retrieve an instance that you assume exists, where non-existence would be an actual error. 
Params:
naturalIdValue – The value of the natural-id for the entity to retrieve
Returns:
The persistent instance or proxy, if an instance exists. Otherwise, null./**
	 * Return the persistent instance with the given natural id value, 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 naturalIdValue The value of the natural-id for the entity to retrieve
	 *
	 * @return The persistent instance or proxy, if an instance exists.  Otherwise, {@code null}.
	 */
	T getReference(Object naturalIdValue);

	
Return the persistent instance with the given natural id value, 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. 
Params:
naturalIdValue – The value of the natural-id for the entity to retrieve
Returns:
The persistent instance or null/**
	 * Return the persistent instance with the given natural id value, or {@code 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 naturalIdValue The value of the natural-id for the entity to retrieve
	 * 
	 * @return The persistent instance or {@code null}
	 */
	T load(Object naturalIdValue);

	
Same semantic as load except that here Optional is returned to handle nullability. 
Params:
naturalIdValue – The identifier
Returns:
The persistent instance, if one, wrapped in Optional/**
	 * Same semantic as {@link #load} except that here {@link Optional} is returned to
	 * handle nullability.
	 *
	 * @param naturalIdValue The identifier
	 *
	 * @return The persistent instance, if one, wrapped in Optional
	 */
	Optional<T> loadOptional(Serializable naturalIdValue);
}