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/*
 * Copyright (c) 2008, 2020 Oracle and/or its affiliates. All rights reserved.
 *
 * This program and the accompanying materials are made available under the
 * terms of the Eclipse Public License v. 2.0 which is available at
 * http://www.eclipse.org/legal/epl-2.0,
 * or the Eclipse Distribution License v. 1.0 which is available at
 * http://www.eclipse.org/org/documents/edl-v10.php.
 *
 * SPDX-License-Identifier: EPL-2.0 OR BSD-3-Clause
 */

// Contributors:
//     Linda DeMichiel - 2.1
//     Linda DeMichiel - 2.0

package jakarta.persistence.criteria;

import java.util.Map;
import jakarta.persistence.metamodel.MapAttribute;

/**
 * The MapJoin interface is the type of the result of
 * joining to a collection over an association or element 
 * collection that has been specified as a java.util.Map.
 *
 * @param  the source type of the join
 * @param  the type of the target Map key
 * @param  the type of the target Map value
 *
 * @since 2.0
 */
public interface MapJoin 
		extends PluralJoin, 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 2.1
     */
    MapJoin on(Expression 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 2.1
     */
    MapJoin on(Predicate... restrictions);

    /**
     * Return the metamodel representation for the map attribute.
     * @return metamodel type representing the Map that is
     *         the target of the join
     */
    MapAttribute getModel();
    
    /**
     * Create a path expression that corresponds to the map key.
     * @return path corresponding to map key
     */
    Path 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 value(); 
    
    /**
     * Create an expression that corresponds to the map entry.
     * @return expression corresponding to the map entry
     */
    Expression> entry();
}