/*
 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS HEADER.
 * 
 * Copyright 1997-2007 Sun Microsystems, Inc. All rights reserved.
 * 
 * The contents of this file are subject to the terms of either the GNU
 * General Public License Version 2 only ("GPL") or the Common Development
 * and Distribution License("CDDL") (collectively, the "License").  You
 * may not use this file except in compliance with the License. You can obtain
 * a copy of the License at https://glassfish.dev.java.net/public/CDDL+GPL.html
 * or glassfish/bootstrap/legal/LICENSE.txt.  See the License for the specific
 * language governing permissions and limitations under the License.
 * 
 * When distributing the software, include this License Header Notice in each
 * file and include the License file at glassfish/bootstrap/legal/LICENSE.txt.
 * Sun designates this particular file as subject to the "Classpath" exception
 * as provided by Sun in the GPL Version 2 section of the License file that
 * accompanied this code.  If applicable, add the following below the License
 * Header, with the fields enclosed by brackets [] replaced by your own
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 */
package javax.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;

/**
 * This annotation is used in the mapping of associations. It 
 * is specified on the owning side of a many-to-many association, 
 * or in a unidirectional one-to-many association.
 *
 * <p> If the <code>JoinTable</code> annotation is missing, the 
 * default values of the annotation elements apply.  The name 
 * of the join table is assumed to be the table names of the 
 * associated primary tables concatenated together (owning side 
 * first) using an underscore.
 *
 * <pre>
 *
 *    Example:
 *    @JoinTable(
 *    name="CUST_PHONE",
 *    joinColumns=
 *        @JoinColumn(name="CUST_ID", referencedColumnName="ID"),
 *    inverseJoinColumns=
 *        @JoinColumn(name="PHONE_ID", referencedColumnName="ID")
 *    )
 * </pre>
 *
 * @since Java Persistence 1.0
 */
@Target({METHOD, FIELD}) 
@Retention(RUNTIME)

public @interface JoinTable {

    /**
     * (Optional) The name of the join table. 
     * 
     * <p> Defaults to the concatenated names of
     * the two associated primary entity tables, 
     * separated by an underscore.
     */
    String name() default "";

    /** (Optional) The catalog of the table. 
     * <p> Defaults to the default catalog.
     */
    String catalog() default "";

    /** (Optional) The schema of the table. 
     * <p> Defaults to the default schema for user.
     */
    String schema() default "";

    /**
     * (Optional) The foreign key columns
     * of the join table which reference the
     * primary table of the entity owning the
     * association (i.e. the owning side of
     * the association).
     *
     * <p> Uses the same defaults as for {@link JoinColumn}.
     */
    JoinColumn[] joinColumns() default {};

    /** 
     * (Optional) The foreign key columns
     * of the join table which reference the
     * primary table of the entity that does
     * not own the association (i.e. the
     * inverse side of the association).
     *
     * <p> Uses the same defaults as for {@link JoinColumn}.
     */
    JoinColumn[] inverseJoinColumns() default {};

    /**
     * (Optional) Unique constraints that are
     * to be placed on the table. These are
     * only used if table generation is in effect.
     * <p> Defaults to no additional constraints.
     */
    UniqueConstraint[] uniqueConstraints() default {};
}