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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.RetentionPolicy.RUNTIME;

/**
 * Specifies that a unique constraint is to be included in
 * the generated DDL for a primary or secondary table.
 *
 *  *    Example:
 *    @Entity
 *    @Table(
 *        name="EMPLOYEE", 
 *        uniqueConstraints=
 *            @UniqueConstraint(columnNames={"EMP_ID", "EMP_NAME"})
 *    )
 *    public class Employee { ... }
 * 
 *
 * @since 1.0
 */
@Target({}) 
@Retention(RUNTIME)
public @interface UniqueConstraint {

    /** (Optional) Constraint name.  A provider-chosen name will be chosen
     * if a name is not specified.
     *
     * @since 2.0
     */
    String name() default "";

    /** (Required) An array of the column names that make up the constraint. */
    String[] columnNames();
}