org.hibernate.id.enhanced
Class TableGenerator

java.lang.Object
  org.hibernate.engine.TransactionHelper
      org.hibernate.id.enhanced.TableGenerator

All Implemented Interfaces:

Configurable, IdentifierGenerator, PersistentIdentifierGenerator

public class TableGenerator
extends TransactionHelper
implements PersistentIdentifierGenerator, Configurable

A "segmented" version of the enhanced table generator. The term "segmented" refers to the fact that this table can hold multiple value generators, segmented by a key.

Configuration parameters:

NAME	DEFAULT	DESCRIPTION
TABLE_PARAM	DEF_TABLE	The name of the table to use to store/retrieve values
VALUE_COLUMN_PARAM	DEF_VALUE_COLUMN	The name of column which holds the sequence value for the given segment
SEGMENT_COLUMN_PARAM	DEF_SEGMENT_COLUMN	The name of the column which holds the segment key
SEGMENT_VALUE_PARAM	DEF_SEGMENT_VALUE	The value indicating which segment is used by this generator; refers to values in the SEGMENT_COLUMN_PARAM column
SEGMENT_LENGTH_PARAM	DEF_SEGMENT_LENGTH	The data length of the SEGMENT_COLUMN_PARAM column; used for schema creation
INITIAL_PARAM	DEFAULT_INITIAL_VALUE	The initial value to be stored for the given segment
INCREMENT_PARAM	DEFAULT_INCREMENT_SIZE	The increment size for the underlying segment; see the discussion on Optimizer for more details.
OPT_PARAM	depends on defined increment size	Allows explicit definition of which optimization strategy to use

Author:

Steve Ebersole

Field Summary

static String	DEF_SEGMENT_COLUMN
static int	DEF_SEGMENT_LENGTH
static String	DEF_SEGMENT_VALUE
static String	DEF_TABLE
static String	DEF_VALUE_COLUMN
static int	DEFAULT_INCREMENT_SIZE
static int	DEFAULT_INITIAL_VALUE
static String	INCREMENT_PARAM
static String	INITIAL_PARAM
static String	OPT_PARAM
static String	SEGMENT_COLUMN_PARAM
static String	SEGMENT_LENGTH_PARAM
static String	SEGMENT_VALUE_PARAM
static String	TABLE_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

TableGenerator()

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	doWorkInCurrentTransaction(Connection conn, String sql) The work to be done
Serializable	generate(SessionImplementor session, Object obj) Generate a new identifier.
Object	generatorKey() Return a key unique to the underlying database objects.
Type	getIdentifierType()
int	getIncrementSize()
int	getInitialValue()
Optimizer	getOptimizer()
String	getSegmentColumnName()
String	getSegmentValue()
int	getSegmentValueLength()
long	getTableAccessCount()
String	getTableName()
String	getValueColumnName()
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 org.hibernate.engine.TransactionHelper

doWorkInNewTransaction

Methods inherited from class java.lang.Object

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

Field Detail

TABLE_PARAM

public static final String TABLE_PARAM

See Also:

Constant Field Values

DEF_TABLE

public static final String DEF_TABLE

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

SEGMENT_COLUMN_PARAM

public static final String SEGMENT_COLUMN_PARAM

See Also:

Constant Field Values

DEF_SEGMENT_COLUMN

public static final String DEF_SEGMENT_COLUMN

See Also:

Constant Field Values

SEGMENT_VALUE_PARAM

public static final String SEGMENT_VALUE_PARAM

See Also:

Constant Field Values

DEF_SEGMENT_VALUE

public static final String DEF_SEGMENT_VALUE

See Also:

Constant Field Values

SEGMENT_LENGTH_PARAM

public static final String SEGMENT_LENGTH_PARAM

See Also:

Constant Field Values

DEF_SEGMENT_LENGTH

public static final int DEF_SEGMENT_LENGTH

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

Constructor Detail

TableGenerator

public TableGenerator()

Method Detail

getTableName

public String getTableName()

getSegmentColumnName

public String getSegmentColumnName()

getSegmentValue

public String getSegmentValue()

getSegmentValueLength

public int getSegmentValueLength()

getValueColumnName

public String getValueColumnName()

getIdentifierType

public Type getIdentifierType()

getInitialValue

public int getInitialValue()

getIncrementSize

public int getIncrementSize()

getOptimizer

public Optimizer getOptimizer()

getTableAccessCount

public long getTableAccessCount()

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 obj)

Description copied from interface: IdentifierGenerator

Generate a new identifier.

Specified by:

generate in interface IdentifierGenerator

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

Returns:

a new identifier

doWorkInCurrentTransaction

public Serializable doWorkInCurrentTransaction(Connection conn,
                                               String sql)
                                        throws SQLException

Description copied from class: TransactionHelper

The work to be done

Specified by:

doWorkInCurrentTransaction in class TransactionHelper

Throws:

SQLException

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

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