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@Target({PACKAGE,TYPE,METHOD,FIELD})@Retention(RUNTIME)@Repeatable(GenericGenerators.class)@Deprecated(since="6.5")public @interfaceGenericGenerator

Defines a named identifier generator, usually an instance of the interfaceIdentifierGenerator. This allows the use of custom identifier generation strategies beyond those provided by the four basic JPA-definedgeneration types.

A named generator may be associated with an entity class by:

• defining a named generator using this annotation, specifying an implementation ofIdentifierGenerator usingtype(), then
• annotating the identifier property of the entity with the JPA-defined@GeneratedValue annotation, and
• usinggenerator to specify thename() of the generator defined using this annotation.

If neithertype() notstrategy() is specified, Hibernate asksthe dialect to decide an appropriate strategy. This is equivalent to usingAUTO in JPA.

For example, if we define a generator using:

 @GenericGenerator(name = "custom-generator",                   type = org.hibernate.eg.CustomStringGenerator.class) }

Then we may make use of it by annotating an identifier field as follows:

 @Id @GeneratedValue(generator = "custom-generator") private String id;

The disadvantage of this approach is the use of stringly-typed names. An alternative, completely typesafe, way to declare a generator and associate it with an entity is provided by the@IdGeneratorType meta-annotation.