org.datanucleus.store.rdbms.mapping

Class CorrespondentColumnsMapper

java.lang.Object

org.datanucleus.store.rdbms.mapping.CorrespondentColumnsMapper

public class CorrespondentColumnsMapper
extends Object

Class to make correspondence between columns in one side of an association to the mapping at the other side. The 2 sides of the association are referred to as "sideA" and "sideB". The JDO 2 metadata allows definition of the correspondence using the syntax.

This means that the column specified on sideA will be mapped to the specified "target" column on sideB. If no target is provided then the first available sideB column is used for the mapping. Where no columns are defined on sideA, then they will be created to match those on sideB. Checks are made for consistency of the sideA data. When there is insufficient ColumnMetaData on sideA then a new ColumnMetaData is added to the column container.

Field Summary

Fields

Modifier and Type	Field and Description
protected static org.datanucleus.util.Localiser	LOCALISER Localiser for messages.

Constructor Summary

Constructors

Constructor and Description
CorrespondentColumnsMapper(org.datanucleus.metadata.ColumnMetaDataContainer columnContainer, org.datanucleus.metadata.ColumnMetaData[] colmds, JavaTypeMapping mappingSideB, boolean updateContainer) Constructor.
CorrespondentColumnsMapper(org.datanucleus.metadata.ColumnMetaDataContainer columnContainer, JavaTypeMapping mappingSideB, boolean updateContainer) Constructor.

Method Summary

Methods

Modifier and Type	Method and Description
org.datanucleus.metadata.ColumnMetaData	getColumnMetaDataByIdentifier(DatastoreIdentifier name) Accessor for the column MetaData in side A that maps to the side B identifier.

Methods inherited from class java.lang.Object

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

Field Detail

LOCALISER

protected static final org.datanucleus.util.Localiser LOCALISER

Localiser for messages.

Constructor Detail

CorrespondentColumnsMapper

public CorrespondentColumnsMapper(org.datanucleus.metadata.ColumnMetaDataContainer columnContainer,
                          org.datanucleus.metadata.ColumnMetaData[] colmds,
                          JavaTypeMapping mappingSideB,
                          boolean updateContainer)

Constructor. Takes the sideB mapping and the side A definition of column metadata and matches them up as defined by the user, and if not defined by the user matches them as best it can. This constructor allows specification of the column metadata array directly, rather than taking what the container has - is used by ColumnCreator where the user has specified multiple columns but only some of them are for this field being mapped.

Parameters:

columnContainer - Container of the columns for side A

colmds - MetaData for the columns to be used

mappingSideB - the mapping in the side B

updateContainer - Whether to add any missing ColumnMetaData objects to the container

CorrespondentColumnsMapper

public CorrespondentColumnsMapper(org.datanucleus.metadata.ColumnMetaDataContainer columnContainer,
                          JavaTypeMapping mappingSideB,
                          boolean updateContainer)

Constructor. Takes the sideB mapping and the side A definition of column metadata and matches them up as defined by the user, and if not defined by the user matches them as best it can.

Parameters:

columnContainer - Container of the columns for side A

mappingSideB - the mapping in the side B

updateContainer - Whether to add any missing ColumnMetaData objects to the container

Method Detail

getColumnMetaDataByIdentifier

public org.datanucleus.metadata.ColumnMetaData getColumnMetaDataByIdentifier(DatastoreIdentifier name)

Accessor for the column MetaData in side A that maps to the side B identifier.

Parameters:

name - The side B identifier

Returns:

ColumnMetaData in side A that equates to the side B column