Java tutorial
/******************************************************************************* * 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.criteria; import java.util.Map; import javax.persistence.metamodel.MapAttribute; /** * The <code>MapJoin</code> interface is the type of the result of * joining to a collection over an association or element * collection that has been specified as a <code>java.util.Map</code>. * * @param <Z> the source type of the join * @param <K> the type of the target Map key * @param <V> the type of the target Map value * * @since Java Persistence 2.0 */ public interface MapJoin<Z, K, V> extends PluralJoin<Z, Map<K, V>, V> { /** * Modify the join to restrict the result according to the * specified ON condition and return the join object. * Replaces the previous ON condition, if any. * @param restriction a simple or compound boolean expression * @return the modified join object * @since Java Persistence 2.1 */ MapJoin<Z, K, V> on(Expression<Boolean> restriction); /** * Modify the join to restrict the result according to the * specified ON condition and return the join object. * Replaces the previous ON condition, if any. * @param restrictions zero or more restriction predicates * @return the modified join object * @since Java Persistence 2.1 */ MapJoin<Z, K, V> on(Predicate... restrictions); /** * Return the metamodel representation for the map attribute. * @return metamodel type representing the <code>Map</code> that is * the target of the join */ MapAttribute<? super Z, K, V> getModel(); /** * Create a path expression that corresponds to the map key. * @return path corresponding to map key */ Path<K> key(); /** * Create a path expression that corresponds to the map value. * This method is for stylistic use only: it just returns this. * @return path corresponding to the map value */ Path<V> value(); /** * Create an expression that corresponds to the map entry. * @return expression corresponding to the map entry */ Expression<Map.Entry<K, V>> entry(); }