org.exolab.castor.jdo.drivers
Class HighLowKeyGenerator

java.lang.Object
  org.exolab.castor.jdo.drivers.HighLowKeyGenerator

All Implemented Interfaces:

KeyGenerator

public class HighLowKeyGenerator

extends java.lang.Object

implements KeyGenerator

The parent abstract class for HIGH-LOW key generators

Version:

$Revision: 1.1.1.1 $ $Date: 2003/03/03 07:08:11 $

Author:

Oleg Nitz

See Also:

HighLowKeyGeneratorFactory

Field Summary

Fields inherited from interface org.exolab.castor.persist.spi.KeyGenerator

AFTER_INSERT, BEFORE_INSERT, DURING_INSERT

Constructor Summary

HighLowKeyGenerator(PersistenceFactory factory, java.util.Properties params, int sqlType)
Initialize the HIGH-LOW key generator.

Method Summary

java.lang.Object	generateKey(java.sql.Connection conn, java.lang.String tableName, java.lang.String primKeyName, java.util.Properties props) Generate a new key for the specified table.
byte	getStyle() Style of key generator: BEFORE_INSERT, DURING_INSERT or AFTER_INSERT ?
boolean	isInSameConnection() Is key generated in the same connection as INSERT?
java.lang.String	patchSQL(java.lang.String insert, java.lang.String primKeyName) Gives a possibility to patch the Castor-generated SQL statement for INSERT (makes sense for DURING_INSERT key generators)

Methods inherited from class java.lang.Object

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

Constructor Detail

HighLowKeyGenerator

public HighLowKeyGenerator(PersistenceFactory factory,
                           java.util.Properties params,
                           int sqlType)
                    throws MappingException

Initialize the HIGH-LOW key generator.

Method Detail

generateKey

public java.lang.Object generateKey(java.sql.Connection conn,
                                    java.lang.String tableName,
                                    java.lang.String primKeyName,
                                    java.util.Properties props)
                             throws PersistenceException

Description copied from interface: KeyGenerator

Generate a new key for the specified table. This method is called when a new object is about to be created. In some environments the name of the owner of the object is known, e.g. the principal in a J2EE server. This method is never called for DURING_INSERT key generators.

Specified by:

generateKey in interface KeyGenerator

Parameters:

conn - An open connection within the given transaction

tableName - The table name

primKeyName - The primary key name

props - A temporary replacement for Principal object

Returns:

A new key

Throws:

PersistenceException - An error occured talking to persistent storage

getStyle

public final byte getStyle()

Style of key generator: BEFORE_INSERT, DURING_INSERT or AFTER_INSERT ?

Specified by:

getStyle in interface KeyGenerator

patchSQL

public final java.lang.String patchSQL(java.lang.String insert,
                                       java.lang.String primKeyName)
                                throws MappingException

Gives a possibility to patch the Castor-generated SQL statement for INSERT (makes sense for DURING_INSERT key generators)

Specified by:

patchSQL in interface KeyGenerator

Parameters:

insert - Castor-generated INSERT statement

primKeyName - The primary key name

Throws:

MappingException

isInSameConnection

public final boolean isInSameConnection()

Is key generated in the same connection as INSERT?

Specified by:

isInSameConnection in interface KeyGenerator