Java tutorial
/******************************************************************************* * 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: * * @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; }