JPA Annotation

SequenceGenerator

Target: TYPE, METHOD, FIELD, PACKAGE
Implemented Interfaces:
Annotation
Defines a primary key generator that may be referenced by name when a generator element is specified for the 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).

If no name is explicitly specified, and the annotation occurs on an entity class or primary key attribute of an entity class, then the name defaults to the name of the entity.

If no name is explicitly specified, and the annotation occurs on a package descriptor, then the annotation defines a recipe for producing a default generator when a GeneratedValue annotation of any program element in the annotated package has strategy=SEQUENCE and a defaulted plain. The name of this default generator is the defaulted generator name, and its other properties are determined by the members of the package SequenceGenerator annotation.

Example:

 {@snippet :
Since:
JPA 1.0
The Auto Generated Values article explains how to use SequenceGenerator.

Public Annotation Attributes

int allocationSize default 50
(Optional) The amount to increment by when allocating sequence numbers from the sequence.
Since:
JPA 1.0
String catalog default ""
(Optional) The catalog of the sequence generator.
Since:
JPA 2.0
int initialValue default 1
(Optional) The value from which the sequence object is to start generating.
Since:
JPA 1.0
String name default ""
(Optional) A unique generator name that can be referenced by one or more classes to be the generator for primary key values.

Defaults to the name of the entity when the annotation occurs on an entity class or primary key attribute.

Since:
JPA 1.0
String options default ""
(Optional) A SQL fragment appended to the generated DDL statement which creates this sequence.
Since:
JPA 3.2
String schema default ""
(Optional) The schema of the sequence generator.
Since:
JPA 2.0
String sequenceName default ""
(Optional) The name of the database sequence object from which to obtain primary key values.

Defaults to a provider-chosen value.

Since:
JPA 1.0