Package org.eclipse.persistence.mappings.transformers

Class ConstantTransformer

java.lang.Object

org.eclipse.persistence.mappings.transformers.FieldTransformerAdapter

org.eclipse.persistence.mappings.transformers.ConstantTransformer

All Implemented Interfaces:

java.io.Serializable, CoreFieldTransformer<Session>, FieldTransformer

public class ConstantTransformer
extends FieldTransformerAdapter

Purpose: Allows a field to always be mapped to a constant value. This allows default values to be provided for un-mapped fields.

See Also:

FieldTransformer, Serialized Form

Author:

James Sutherland

Since:

10.1.3

Field Summary

Fields

Modifier and Type	Field	Description
protected java.lang.Object	value

Fields inherited from interface org.eclipse.persistence.core.mappings.transformers.CoreFieldTransformer

BUILD_FIELD_VALUE_METHOD

Constructor Summary

Constructors

Constructor	Description
ConstantTransformer()
ConstantTransformer(java.lang.Object value)	PUBLIC: Return a constant transformer for the constant value.

Method Summary

Modifier and Type	Method	Description
java.lang.Object	buildFieldValue(java.lang.Object object, java.lang.String fieldName, Session session)	INTERNAL: Always return the constant value.
java.lang.Object	getValue()	PUBLIC: Return the value of the constant.
void	setValue(java.lang.Object value)	PUBLIC: Set the value of the constant.

Methods inherited from class org.eclipse.persistence.mappings.transformers.FieldTransformerAdapter

initialize

Methods inherited from class java.lang.Object

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

Field Detail

value

protected java.lang.Object value

Constructor Detail

ConstantTransformer

public ConstantTransformer()

ConstantTransformer

public ConstantTransformer(java.lang.Object value)

PUBLIC: Return a constant transformer for the constant value.

Method Detail

getValue

public java.lang.Object getValue()

PUBLIC: Return the value of the constant.

setValue

public void setValue(java.lang.Object value)

PUBLIC: Set the value of the constant.

buildFieldValue

public java.lang.Object buildFieldValue(java.lang.Object object,
                                        java.lang.String fieldName,
                                        Session session)

INTERNAL: Always return the constant value.

Specified by:

buildFieldValue in interface CoreFieldTransformer<Session>

Specified by:

buildFieldValue in interface FieldTransformer

Overrides:

buildFieldValue in class FieldTransformerAdapter

Parameters:

object - - an instance of the domain class which contains the attribute

fieldName - - the name of the field being transformed. Used if the user wants to use this transformer for multiple fields.

session - - the current session

Returns:

- The value to be written for the field associated with this transformer