Annotation Interface IdGeneratorType
For example, if we have a custom identifier generator:
public class CustomSequenceGenerator implements BeforeExecutionGenerator { public CustomSequenceGenerator(CustomSequence config, Member annotatedMember, GeneratorCreationContext context) { ... } ... }
Then we may also define an annotation which associates this generator with an entity and supplies configuration parameters:
@IdGeneratorType(CustomSequenceGenerator.class) @Retention(RUNTIME) @Target({METHOD,FIELD}) public @interface CustomSequence { String name(); int startWith() default 1; int incrementBy() default 50; }
and we may use it as follows:
@Id @CustomSequence(name = "mysequence", startWith = 0) private Integer id;
We did not use the JPA-defined GeneratedValue
here, since that API is designed around the use of stringly-typed names.
The @CustomSequence
annotation itself implies that id
is
a generated value.
An id generator annotation may have members, which are used to configure the id generator, if either:
- the id generator implements
AnnotationBasedGenerator
, or - the id generator class has a constructor with the same signature as
AnnotationBasedGenerator.initialize(A, java.lang.reflect.Member, org.hibernate.generator.GeneratorCreationContext)
.
For a more complete example, see the annotation UuidGenerator
and
the corresponding generator class UuidGenerator
.
A @IdGeneratorType
annotation must have retention policy
RetentionPolicy.RUNTIME
.
If a Generator
may be used to generate values of non-identifier
fields, its generator annotation should also be meta-annotated
@ValueGenerationType
.
- Since:
- 6.0
- See Also:
-
Required Element Summary
Required Elements
-
Element Details
-
value
A class which implementsGenerator
.
-