javax.persistence

Annotation Type GeneratedValue

@Target(value={METHOD,FIELD})
 @Retention(value=RUNTIME)
public @interface GeneratedValue

Provides for the specification of generation strategies for the values of primary keys.

The GeneratedValue annotation may be applied to a primary key property or field of an entity or mapped superclass in conjunction with the Id annotation. The use of the GeneratedValue annotation is only required to be supported for simple primary keys. Use of the GeneratedValue annotation is not supported for derived primary keys.

     Example 1:

     @Id
     @GeneratedValue(strategy=SEQUENCE, generator="CUST_SEQ")
     @Column(name="CUST_ID")
     public Long getId() { return id; }

     Example 2:

     @Id
     @GeneratedValue(strategy=TABLE, generator="CUST_GEN")
     @Column(name="CUST_ID")
     Long id;
 

Since:

Java Persistence 1.0

See Also:

Id, TableGenerator, SequenceGenerator

Optional Element Summary

Optional Elements

Modifier and Type	Optional Element and Description
String	generator (Optional) The name of the primary key generator to use as specified in the SequenceGenerator or TableGenerator annotation.
GenerationType	strategy (Optional) The primary key generation strategy that the persistence provider must use to generate the annotated entity primary key.

Element Detail

strategy

public abstract GenerationType strategy

(Optional) The primary key generation strategy that the persistence provider must use to generate the annotated entity primary key.

Returns:

strategy

Default:

javax.persistence.GenerationType.AUTO

generator

public abstract String generator

(Optional) The name of the primary key generator to use as specified in the SequenceGenerator or TableGenerator annotation.

Defaults to the id generator supplied by persistence provider.

Returns:

generator

Default:

""