org.hibernate.id.enhanced
Class SequenceStyleGenerator

java.lang.Object
  org.hibernate.id.enhanced.SequenceStyleGenerator

All Implemented Interfaces:

Configurable, IdentifierGenerator, PersistentIdentifierGenerator

public class SequenceStyleGenerator
extends Object
implements PersistentIdentifierGenerator, Configurable

Generates identifier values based on an sequence-style database structure. Variations range from actually using a sequence to using a table to mimic a sequence. These variations are encapsulated by the DatabaseStructure interface internally.

General configuration parameters:

NAME	DEFAULT	DESCRIPTION
SEQUENCE_PARAM	DEF_SEQUENCE_NAME	The name of the sequence/table to use to store/retrieve values
INITIAL_PARAM	DEFAULT_INITIAL_VALUE	The initial value to be stored for the given segment; the effect in terms of storage varies based on Optimizer and DatabaseStructure
INCREMENT_PARAM	DEFAULT_INCREMENT_SIZE	The increment size for the underlying segment; the effect in terms of storage varies based on Optimizer and DatabaseStructure
OPT_PARAM	depends on defined increment size	Allows explicit definition of which optimization strategy to use
FORCE_TBL_PARAM	false	Allows explicit definition of which optimization strategy to use

Configuration parameters used specifically when the underlying structure is a table:

NAME	DEFAULT	DESCRIPTION
VALUE_COLUMN_PARAM	DEF_VALUE_COLUMN	The name of column which holds the sequence value for the given segment

Author:

Steve Ebersole

Field Summary

static String	DEF_SEQUENCE_NAME
static String	DEF_VALUE_COLUMN
static int	DEFAULT_INCREMENT_SIZE
static int	DEFAULT_INITIAL_VALUE
static String	FORCE_TBL_PARAM
static String	INCREMENT_PARAM
static String	INITIAL_PARAM
static String	OPT_PARAM
static String	SEQUENCE_PARAM
static String	VALUE_COLUMN_PARAM

Fields inherited from interface org.hibernate.id.PersistentIdentifierGenerator

CATALOG, PK, SCHEMA, SQL, TABLE, TABLES

Fields inherited from interface org.hibernate.id.IdentifierGenerator

ENTITY_NAME

Constructor Summary

SequenceStyleGenerator()

Method Summary

void	configure(Type type, Properties params, Dialect dialect) Configure this instance, given the value of parameters specified by the user as <param> elements.
Serializable	generate(SessionImplementor session, Object object) Generate a new identifier.
Object	generatorKey() Return a key unique to the underlying database objects.
DatabaseStructure	getDatabaseStructure()
Type	getIdentifierType()
Optimizer	getOptimizer()
String[]	sqlCreateStrings(Dialect dialect) The SQL required to create the underlying database objects.
String[]	sqlDropStrings(Dialect dialect) The SQL required to remove the underlying database objects.

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Field Detail

SEQUENCE_PARAM

public static final String SEQUENCE_PARAM

See Also:

Constant Field Values

DEF_SEQUENCE_NAME

public static final String DEF_SEQUENCE_NAME

See Also:

Constant Field Values

INITIAL_PARAM

public static final String INITIAL_PARAM

See Also:

Constant Field Values

DEFAULT_INITIAL_VALUE

public static final int DEFAULT_INITIAL_VALUE

See Also:

Constant Field Values

INCREMENT_PARAM

public static final String INCREMENT_PARAM

See Also:

Constant Field Values

DEFAULT_INCREMENT_SIZE

public static final int DEFAULT_INCREMENT_SIZE

See Also:

Constant Field Values

OPT_PARAM

public static final String OPT_PARAM

See Also:

Constant Field Values

FORCE_TBL_PARAM

public static final String FORCE_TBL_PARAM

See Also:

Constant Field Values

VALUE_COLUMN_PARAM

public static final String VALUE_COLUMN_PARAM

See Also:

Constant Field Values

DEF_VALUE_COLUMN

public static final String DEF_VALUE_COLUMN

See Also:

Constant Field Values

Constructor Detail

SequenceStyleGenerator

public SequenceStyleGenerator()

Method Detail

getDatabaseStructure

public DatabaseStructure getDatabaseStructure()

getOptimizer

public Optimizer getOptimizer()

getIdentifierType

public Type getIdentifierType()

configure

public void configure(Type type,
                      Properties params,
                      Dialect dialect)
               throws MappingException

Description copied from interface: Configurable

Configure this instance, given the value of parameters specified by the user as <param> elements. This method is called just once, following instantiation.

Specified by:

configure in interface Configurable

params - param values, keyed by parameter name

Throws:

MappingException

generate

public Serializable generate(SessionImplementor session,
                             Object object)
                      throws HibernateException

Description copied from interface: IdentifierGenerator

Generate a new identifier.

Specified by:

generate in interface IdentifierGenerator

object - the entity or toplevel collection for which the id is being generated

Returns:

a new identifier

Throws:

HibernateException

generatorKey

public Object generatorKey()

Description copied from interface: PersistentIdentifierGenerator

Return a key unique to the underlying database objects. Prevents us from trying to create/remove them multiple times.

Specified by:

generatorKey in interface PersistentIdentifierGenerator

Returns:

Object an identifying key for this generator

sqlCreateStrings

public String[] sqlCreateStrings(Dialect dialect)
                          throws HibernateException

Description copied from interface: PersistentIdentifierGenerator

The SQL required to create the underlying database objects.

Specified by:

sqlCreateStrings in interface PersistentIdentifierGenerator

Returns:

String[]

Throws:

HibernateException

sqlDropStrings

public String[] sqlDropStrings(Dialect dialect)
                        throws HibernateException

Description copied from interface: PersistentIdentifierGenerator

The SQL required to remove the underlying database objects.

Specified by:

sqlDropStrings in interface PersistentIdentifierGenerator

Returns:

String

Throws:

HibernateException