Package org.hibernate.id

Interface IdentifierGenerator

All Superinterfaces:

BeforeExecutionGenerator, Configurable, ExportableProducer, Generator, Serializable

All Known Subinterfaces:

OptimizableGenerator, PersistentIdentifierGenerator

All Known Implementing Classes:

AbstractUUIDGenerator, Assigned, CompositeNestedGeneratedValueGenerator, ForeignGenerator, GUIDGenerator, IncrementGenerator, OrderedSequenceGenerator, SequenceStyleGenerator, TableGenerator, UUIDGenerator, UUIDHexGenerator

public interface IdentifierGenerator
extends BeforeExecutionGenerator, ExportableProducer, Configurable

A classic extension point from the very earliest days of Hibernate, this interface is no longer the only way to generate identifiers. Any BeforeExecutionGenerator with timing EventTypeSets.INSERT_ONLY may now be used.

This interface extends BeforeExecutionGenerator with some additional machinery for configuration, and for caching generated SQL.

Any identifier generator, including a generator which directly implements BeforeExecutionGenerator, may also implement ExportableProducer. For the sake of convenience, PersistentIdentifierGenerator extends ExportableProducer, in case the implementation needs to export objects to the database as part of the process of schema export.

The configure(Type, Properties, ServiceRegistry) method accepts a properties object containing named values. These include:

• several "standard" parameters with keys defined as static members of this interface: "entity_name", "jpa_entity_name", "GENERATOR_NAME", "CONTRIBUTOR", along with
• additional hardcoded parameters supplied by Hibernate to its built-in generators, depending on the generator class, and, possibly,
• parameters specified using GenericGenerator.parameters().

Instances of IdentifierGenerator are usually created and configured by the IdentifierGeneratorFactory service. It's not usually correct to use an IdentifierGenerator with the IdGeneratorType meta-annotation.

Author:

Gavin King

See Also:

• PostInsertIdentifierGenerator
• PersistentIdentifierGenerator

Field Summary

Fields

Modifier and Type	Field	Description
static final String	CONTRIBUTOR_NAME	The contributor that contributed this generator
static final String	ENTITY_NAME	The configuration parameter holding the entity name
static final String	GENERATOR_NAME	The configuration parameter holding the name of this identifier generator.
static final String	JPA_ENTITY_NAME	The configuration parameter holding the JPA entity name

Method Summary

Modifier and Type	Method	Description
default void	configure(Type type, Properties parameters, ServiceRegistry serviceRegistry)	Configure this instance, given the value of parameters specified by the user as <param> elements.
Object	generate(SharedSessionContractImplementor session, Object object)	Generate a new identifier.
default Object	generate(SharedSessionContractImplementor session, Object owner, Object currentValue, EventType eventType)	Generate a value.
default EnumSet<EventType>	getEventTypes()	The event types for which this generator should be called to produce a new value.
default void	registerExportables(Database database)	Register database objects used by this identifier generator, for example, a sequence or tables.
default boolean	supportsJdbcBatchInserts()	Deprecated. this method is no longer called

Methods inherited from interface org.hibernate.generator.BeforeExecutionGenerator

generatedOnExecution

Methods inherited from interface org.hibernate.id.Configurable

create, initialize

Methods inherited from interface org.hibernate.generator.Generator

allowAssignedIdentifiers, generatedOnExecution, generatesOnInsert, generatesOnUpdate, generatesSometimes

Field Details

ENTITY_NAME

static final String ENTITY_NAME

The configuration parameter holding the entity name

See Also:

• Constant Field Values

JPA_ENTITY_NAME

static final String JPA_ENTITY_NAME

The configuration parameter holding the JPA entity name

See Also:

• Constant Field Values

GENERATOR_NAME

static final String GENERATOR_NAME

The configuration parameter holding the name of this identifier generator.

See Also:

• GenericGenerator.name()
• GeneratedValue.generator()
• Constant Field Values

CONTRIBUTOR_NAME

static final String CONTRIBUTOR_NAME

The contributor that contributed this generator

See Also:

• Constant Field Values

Method Details

configure

default void configure(Type type,
 Properties parameters,
 ServiceRegistry serviceRegistry)

Configure this instance, given the value of parameters specified by the user as <param> elements.

This method is called just once, following instantiation, and before registerExportables(Database).

Specified by:

configure in interface Configurable

Parameters:

type - The id property type descriptor

parameters - param values, keyed by parameter name

serviceRegistry - Access to service that may be needed.

Throws:

MappingException - If configuration fails.

registerExportables

default void registerExportables(Database database)

Register database objects used by this identifier generator, for example, a sequence or tables.

This method is called just once, after configure(Type, Properties, ServiceRegistry).

Specified by:

registerExportables in interface ExportableProducer

Parameters:

database - The database instance

generate

Object generate(SharedSessionContractImplementor session,
 Object object)

Generate a new identifier.

Parameters:

session - The session from which the request originates

object - the entity or collection (idbag) for which the id is being generated

Returns:

a new identifier

Throws:

HibernateException - Indicates trouble generating the identifier

generate

default Object generate(SharedSessionContractImplementor session,
 Object owner,
 Object currentValue,
 EventType eventType)

Generate a value.

The currentValue is usually null for id generation.

Specified by:

generate in interface BeforeExecutionGenerator

Parameters:

session - The session from which the request originates.

owner - The instance of the object owning the attribute for which we are generating a value.

currentValue - The current value assigned to the property, or null

eventType - The type of event that has triggered generation of a new value

Returns:

The generated value

getEventTypes

default EnumSet<EventType> getEventTypes()

Description copied from interface: Generator

The event types for which this generator should be called to produce a new value.

Identifier generators must return EventTypeSets.INSERT_ONLY.

Specified by:

getEventTypes in interface Generator

Returns:

EventTypeSets.INSERT_ONLY

supportsJdbcBatchInserts

@Deprecated(since="6.2")
default boolean supportsJdbcBatchInserts()

Deprecated.

this method is no longer called

Check if JDBC batch inserts are supported.

Returns:

JDBC batch inserts are supported.