src/javax/persistence/PrimaryKeyJoinColumns.java

/*******************************************************************************
 * Copyright (c) 1998, 2009 Oracle. 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:
 *     dclarke - Java Persistence 2.0 - Proposed Final Draft (March 13, 2009)
 *     		     Specification available from http://jcp.org/en/jsr/detail?id=317
 *
 * Java(TM) Persistence API, Version 2.0 - EARLY ACCESS
 * This is an implementation of an early-draft specification developed under the 
 * Java Community Process (JCP).  The code is untested and presumed not to be a  
 * compatible implementation of JSR 317: Java(TM) Persistence API, Version 2.0.   
 * We encourage you to migrate to an implementation of the Java(TM) Persistence 
 * API, Version 2.0 Specification that has been tested and verified to be compatible 
 * as soon as such an implementation is available, and we encourage you to retain 
 * this notice in any implementation of Java(TM) Persistence API, Version 2.0 
 * Specification that you distribute.
 ******************************************************************************/
package javax.persistence;

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

/**
 * This annotation groups {@link PrimaryKeyJoinColumn} annotations.
 * It is used to map composite foreign keys.
 *
 * <pre>
 *    Example 1: ValuedCustomer subclass
 *
 *    &#064;Entity
 *    &#064;Table(name="VCUST")
 *    &#064;DiscriminatorValue("VCUST")
 *    &#064;PrimaryKeyJoinColumns({
 *        &#064;PrimaryKeyJoinColumn(name="CUST_ID", 
 *            referencedColumnName="ID"),
 *        &#064;PrimaryKeyJoinColumn(name="CUST_TYPE",
 *            referencedColumnName="TYPE")
 *    })
 *    public class ValuedCustomer extends Customer { ... }
 * </pre>
 *
 * @since Java Persistence 1.0
 */
@Target({TYPE, METHOD, FIELD})
@Retention(RUNTIME)

public @interface PrimaryKeyJoinColumns {

    /** One or more {@link PrimaryKeyJoinColumn} annotations. */
    PrimaryKeyJoinColumn[] value();
}