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JPMS Module-Info's for a few of the Jakarta Libraries just until they add them in themselves

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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;

import java.lang.annotation.Target;
import java.lang.annotation.Retention;
import static java.lang.annotation.ElementType.FIELD;
import static java.lang.annotation.ElementType.METHOD;
import static java.lang.annotation.RetentionPolicy.RUNTIME;

/**
 * Specifies the map key for associations of type 
 * {@link java.util.Map java.util.Map} when the map key is itself the primary
 * key or a persistent field or property of the entity that is
 * the value of the map.
 * 
 * 

If a persistent field or property other than the primary * key is used as a map key then it is expected to have a * uniqueness constraint associated with it. * *

The {@link MapKeyClass} annotation is not used when * MapKey is specified and vice versa. * *

 *
 *    Example 1:
 *
 *    @Entity
 *    public class Department {
 *        ...
 *        @OneToMany(mappedBy="department")
 *        @MapKey  // map key is primary key
 *        public Map<Integer, Employee> getEmployees() {... }
 *        ...
 *    }
 *
 *    @Entity
 *    public class Employee {
 *        ...
 *        @Id Integer getEmpId() { ... }
 *        @ManyToOne
 *        @JoinColumn(name="dept_id")
 *        public Department getDepartment() { ... }
 *        ...
 *    }
 *
 *    Example 2:
 *
 *    @Entity
 *        public class Department {
 *        ...
 *        @OneToMany(mappedBy="department")
 *        @MapKey(name="name")
 *        public Map<String, Employee> getEmployees() {... }
 *        ...
 *    }
 *
 *    @Entity
 *        public class Employee {
 *        @Id public Integer getEmpId() { ... }
 *        ...
 *        @ManyToOne
 *        @JoinColumn(name="dept_id")
 *        public Department getDepartment() { ... }
 *        ...
 *    }
 * 
* * @since 1.0 */ @Target({METHOD, FIELD}) @Retention(RUNTIME) public @interface MapKey { /** * (Optional) The name of the persistent field or property of the * associated entity that is used as the map key. *

Default: If the * name element is not specified, the primary key of the * associated entity is used as the map key. If the * primary key is a composite primary key and is mapped * as IdClass, an instance of the primary key * class is used as the key. */ String name() default ""; }





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