ojb.broker.util.sequence
Class SequenceManagerHighLowImpl

java.lang.Object
  |
  +--ojb.broker.util.sequence.SequenceManagerDefaultImpl
        |
        +--ojb.broker.util.sequence.SequenceManagerHighLowImpl

All Implemented Interfaces:

SequenceManager

public class SequenceManagerHighLowImpl

extends SequenceManagerDefaultImpl

The SequenceManager implementing the generic High / Low algorithm. It reserves a set of keys in an auxiliary table named 'OJB_HL_SEQ' for each class and key field.
The reserved keys are then used one after the other, the SequenceManagerHighLowImpl makes new reservations as needed.

Author:

R Bischof

Field Summary

Fields inherited from class ojb.broker.util.sequence.SequenceManagerDefaultImpl

broker

Constructor Summary

SequenceManagerHighLowImpl(PersistenceBrokerImpl broker)
Constructor for the SequenceManagerHighLowImpl object

Method Summary

int	getUniqueId(java.lang.Class clazz, java.lang.String fieldName) Gets a new uniqueId for the given Class and fieldname
java.lang.String	getUniqueString(java.lang.Class clazz, java.lang.String fieldName) Gets a new unique String for the given Class and fieldname
void	setIncrement(int defaultGrabSize) Sets the default GrabSize for new Sequences

Methods inherited from class ojb.broker.util.sequence.SequenceManagerDefaultImpl

getMaxForExtent, getUniqueLong, getUniqueObject

Methods inherited from class java.lang.Object

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

Constructor Detail

SequenceManagerHighLowImpl

public SequenceManagerHighLowImpl(PersistenceBrokerImpl broker)

Constructor for the SequenceManagerHighLowImpl object

Parameters:

broker - This BrokerImpl is required to look up the initial MAX keys

Method Detail

setIncrement

public void setIncrement(int defaultGrabSize)

Sets the default GrabSize for new Sequences

Parameters:

defaultGrabSize - The new default GrabSize value

getUniqueId

public int getUniqueId(java.lang.Class clazz,
                       java.lang.String fieldName)
                throws PersistenceBrokerException

Gets a new uniqueId for the given Class and fieldname

Specified by:

getUniqueId in interface SequenceManager

Overrides:

getUniqueId in class SequenceManagerDefaultImpl

Parameters:

clazz - The Class to find a key for

fieldName - The field of the class

Returns:

A new unique Id

PersistenceBrokerException

getUniqueString

public java.lang.String getUniqueString(java.lang.Class clazz,
                                        java.lang.String fieldName)

Gets a new unique String for the given Class and fieldname

Specified by:

getUniqueString in interface SequenceManager

Overrides:

getUniqueString in class SequenceManagerDefaultImpl

Parameters:

clazz - The Class to find a key for

fieldName - The field of the class

Returns:

A new unique String