721 words

javax.persistence.TableGenerator - JPA annotation

javax.persistence
Annotation TableGenerator

Target:
Classes and fields (including property get methods)
Defines a primary key generator that may be referenced by name when a generator element is specified for the 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;
        ...
    }
Since:
JPA 1.0
See Also:
GeneratedValue
Learn how to define and use automatic value generation in Chapter 2 of the ObjectDB/JPA manual.
(Optional) The amount to increment by when allocating id numbers from the generator.
(Optional) The amount to increment by when allocating id numbers from the generator.
Default value:
50
Since:
JPA 1.0
String catalog
(Optional) The catalog of the table.
(Optional) The catalog of the table.

Defaults to the default catalog.

Default value:
""
Since:
JPA 1.0
(Optional) The initial value to be used to initialize the column that stores the last value generated.
(Optional) The initial value to be used to initialize the column that stores the last value generated.
Default value:
0
Since:
JPA 1.0
String name
(Required) A unique generator name that can be referenced by one or more classes to be the generator for id values.
(Required) A unique generator name that can be referenced by one or more classes to be the generator for id values.
Since:
JPA 1.0
(Optional) Name of the primary key column in the table.
(Optional) Name of the primary key column in the table.

Defaults to a provider-chosen name.

Default value:
""
Since:
JPA 1.0
(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.
(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

Default value:
""
Since:
JPA 1.0
String schema
(Optional) The schema of the table.
(Optional) The schema of the table.

Defaults to the default schema for user.

Default value:
""
Since:
JPA 1.0
String table
(Optional) Name of table that stores the generated id values.
(Optional) Name of table that stores the generated id values.

Defaults to a name chosen by persistence provider.

Default value:
""
Since:
JPA 1.0
(Optional) Unique constraints that are to be placed on the table.
(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.

Default value:
{}
Since:
JPA 1.0
(Optional) Name of the column that stores the last value generated.
(Optional) Name of the column that stores the last value generated.

Defaults to a provider-chosen name.

Default value:
""
Since:
JPA 1.0

This documentation page is derived (with some adjustments) from the open source JPA 2 RI (EclipseLink)
and is available under the terms of the Eclipse Public License, v. 1.0 and Eclipse Distribution License, v. 1.0.
Object Relational Mapping (ORM) JPA 2 providers include Hibernate, EclipseLink, TopLink, OpenJPA and DataNucleus.
Object DB is not an ORM JPA implementation but an Object Database for Java with built in JPA 2 support.