org.hibernate.engine.spi

Class VersionValue

java.lang.Object

org.hibernate.engine.spi.VersionValue

All Implemented Interfaces:

UnsavedValueStrategy

public class VersionValue
extends Object
implements UnsavedValueStrategy

A strategy for determining if a version value is a version of a new transient instance or a previously persistent transient instance. The strategy is determined by the unsaved-value attribute in the mapping file.

Author:

Gavin King

Field Summary

Fields

Modifier and Type	Field and Description
static VersionValue	NEGATIVE Assume the transient instance is newly instantiated if the version is negative, otherwise assume it is a detached instance.
static VersionValue	NULL Assume the transient instance is newly instantiated if the version is null, otherwise assume it is a detached instance.
static VersionValue	UNDEFINED Assume the transient instance is newly instantiated if the version is null, otherwise defer to the identifier unsaved-value.

Constructor Summary

Constructors

Modifier	Constructor and Description
protected	VersionValue()
	VersionValue(Object value) Assume the transient instance is newly instantiated if its version is null or equal to value

Method Summary

Modifier and Type	Method and Description
Object	getDefaultValue(Object currentValue) Get a default value meant to indicate transience.
Boolean	isUnsaved(Object version) Make the transient/detached determination
String	toString()

Methods inherited from class java.lang.Object

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

Field Detail

NULL

public static final VersionValue NULL

Assume the transient instance is newly instantiated if the version is null, otherwise assume it is a detached instance.

UNDEFINED

public static final VersionValue UNDEFINED

Assume the transient instance is newly instantiated if the version is null, otherwise defer to the identifier unsaved-value.

NEGATIVE

public static final VersionValue NEGATIVE

Assume the transient instance is newly instantiated if the version is negative, otherwise assume it is a detached instance.

Constructor Detail

VersionValue

protected VersionValue()

VersionValue

public VersionValue(Object value)

Assume the transient instance is newly instantiated if its version is null or equal to value

Parameters:

value - value to compare to

Method Detail

isUnsaved

public Boolean isUnsaved(Object version)
                  throws MappingException

Description copied from interface: UnsavedValueStrategy

Make the transient/detached determination

Specified by:

isUnsaved in interface UnsavedValueStrategy

Parameters:

version - The value to be tested

Returns:

true indicates the value corresponds to unsaved data (aka, transient state; false indicates the value does not corresponds to unsaved data (aka, detached state); null indicates that this strategy was not able to determine conclusively.

Throws:

MappingException

getDefaultValue

public Object getDefaultValue(Object currentValue)

Description copied from interface: UnsavedValueStrategy

Get a default value meant to indicate transience.

Specified by:

getDefaultValue in interface UnsavedValueStrategy

Parameters:

currentValue - The current state value.

Returns:

The default transience value.

toString

public String toString()

Overrides:

toString in class Object