javax.persistence.TableGenerator Maven / Gradle / Ivy
/*******************************************************************************
* 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.FIELD;
import static java.lang.annotation.ElementType.METHOD;
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 table 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).
*
*
* Example 1:
*
* @Entity public class Employee {
* ...
* @TableGenerator(
* name="empGen",
* table="ID_GEN",
* pkColumnName="GEN_KEY",
* valueColumnName="GEN_VALUE",
* pkColumnValue="EMP_ID",
* allocationSize=1)
* @Id
* @GeneratedValue(strategy=TABLE, generator="empGen")
* int id;
* ...
* }
*
* Example 2:
*
* @Entity public class Address {
* ...
* @TableGenerator(
* name="addressGen",
* table="ID_GEN",
* pkColumnName="GEN_KEY",
* valueColumnName="GEN_VALUE",
* pkColumnValue="ADDR_ID")
* @Id
* @GeneratedValue(strategy=TABLE, generator="addressGen")
* int id;
* ...
* }
*
*
* @see GeneratedValue
*
* @since Java Persistence 1.0
*/
@Repeatable(TableGenerators.class)
@Target({TYPE, METHOD, FIELD})
@Retention(RUNTIME)
public @interface TableGenerator {
/**
* (Required) A unique generator name that can be referenced
* by one or more classes to be the generator for id values.
*/
String name();
/**
* (Optional) Name of table that stores the generated id values.
* Defaults to a name chosen by persistence provider.
*/
String table() default "";
/** (Optional) The catalog of the table.
*
Defaults to the default catalog.
*/
String catalog() default "";
/** (Optional) The schema of the table.
*
Defaults to the default schema for user.
*/
String schema() default "";
/**
* (Optional) Name of the primary key column in the table.
*
Defaults to a provider-chosen name.
*/
String pkColumnName() default "";
/**
* (Optional) Name of the column that stores the last value generated.
*
Defaults to a provider-chosen name.
*/
String valueColumnName() default "";
/**
* (Optional) The primary key value in the generator table
* that distinguishes this set of generated values from others
* that may be stored in the table.
*
Defaults to a provider-chosen value to store in the
* primary key column of the generator table
*/
String pkColumnValue() default "";
/**
* (Optional) The initial value to be used to initialize the column
* that stores the last value generated.
*/
int initialValue() default 0;
/**
* (Optional) The amount to increment by when allocating id
* numbers from the generator.
*/
int allocationSize() default 50;
/**
* (Optional) Unique constraints that are to be placed on the
* table. These are only used if table generation is in effect.
* These constraints apply in addition to primary key constraints.
*
Defaults to no additional constraints.
*/
UniqueConstraint[] uniqueConstraints() default {};
/**
* (Optional) Indexes for the table. These are only used if
* table generation is in effect. Note that it is not necessary
* to specify an index for a primary key, as the primary key
* index will be created automatically.
*
* @since Java Persistence 2.1
*/
Index[] indexes() default {};
}