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javax.persistence.GenerationType - JPA enum

javax.persistence
Enum GenerationType

java.lang.Object
    java.lang.Enum<javax.persistence.GenerationType>
        javax.persistence.GenerationType
Implemented Interfaces:
Serializable, Comparable<GenerationType>
Defines the types of primary key generation strategies.
Since:
JPA 1.0
See Also:
GeneratedValue
Learn how to define and use automatic value generation in Chapter 2 of the ObjectDB/JPA manual.
GenerationType AUTO
Indicates that the persistence provider should pick an appropriate strategy for the particular database.
Indicates that the persistence provider should pick an appropriate strategy for the particular database. The AUTO generation strategy may expect a database resource to exist, or it may attempt to create one. A vendor may provide documentation on how to create such resources in the event that it does not support schema generation or cannot create the schema resource at runtime.
Since:
JPA 1.0
GenerationType IDENTITY
Indicates that the persistence provider must assign primary keys for the entity using a database identity column.
Indicates that the persistence provider must assign primary keys for the entity using a database identity column.
Since:
JPA 1.0
GenerationType SEQUENCE
Indicates that the persistence provider must assign primary keys for the entity using a database sequence.
Indicates that the persistence provider must assign primary keys for the entity using a database sequence.
Since:
JPA 1.0
GenerationType TABLE
Indicates that the persistence provider must assign primary keys for the entity using an underlying database table to ensure uniqueness.
Indicates that the persistence provider must assign primary keys for the entity using an underlying database table to ensure uniqueness.
Since:
JPA 1.0
GenerationType valueOf(String name)

Returns the enum constant of this type with the specified name.

Returns the enum constant of this type with the specified name. The string must match exactly an identifier used to declare an enum constant in this type.

Parameters:
name - the name of the enum constant to be returned.
Returns:
the enum constant with the specified name
Throws:
java.lang.IllegalArgumentException - if this enum type has no constant with the specified name
java.lang.NullPointerException - if the argument is null

GenerationType[] values()

Returns an array containing the constants of this enum type.

Returns an array containing the constants of this enum type.

This method may be used to iterate over the constants as follows:

for (GenerationType c : GenerationType.values())
    System.out.println(c)
Returns:
an array containing the constants of this enum type, in the order they are declared

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.