/*******************************************************************************
 * Copyright (c) 2008 - 2017 Oracle Corporation. 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:
 *     Lukas Jungmann  - Java Persistence 2.2
 *     Linda DeMichiel - Java Persistence 2.1
 *     Linda DeMichiel - Java Persistence 2.0
 *
 ******************************************************************************/ 
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;

import java.lang.annotation.Repeatable;

/**
 * Defines a primary key generator that may be referenced by name when
 * a generator element is specified for the {@link GeneratedValue}
 * annotation. A sequence generator may be specified on the entity
 * class or on the primary key field or property. The scope of the
 * generator name is global to the persistence unit (across all
 * generator types).
 *
 * <pre>
 *   Example:
 *
 *   &#064;SequenceGenerator(name="EMP_SEQ", allocationSize=25)
 * </pre>
 *
 * @since Java Persistence 1.0
 */
@Repeatable(SequenceGenerators.class)
@Target({TYPE, METHOD, FIELD}) 
@Retention(RUNTIME)
public @interface SequenceGenerator {

    /** 
     * (Required) A unique generator name that can be referenced 
     * by one or more classes to be the generator for primary key 
     * values.
     */
    String name();

    /**
     * (Optional) The name of the database sequence object from 
     * which to obtain primary key values.
     * <p> Defaults to a provider-chosen value.
     */
    String sequenceName() default "";

    /** (Optional) The catalog of the sequence generator. 
     *
     * @since Java Persistence 2.0
     */
    String catalog() default "";

    /** (Optional) The schema of the sequence generator. 
     *
     * @since Java Persistence 2.0
     */
    String schema() default "";

    /** 
     * (Optional) The value from which the sequence object 
     * is to start generating.
     */
    int initialValue() default 1;

    /**
     * (Optional) The amount to increment by when allocating 
     * sequence numbers from the sequence.
     */
    int allocationSize() default 50;
}