org.datanucleus.store.mapped.mapping
Class MultiMapping

java.lang.Object
  org.datanucleus.store.mapped.mapping.JavaTypeMapping
      org.datanucleus.store.mapped.mapping.MultiMapping

Direct Known Subclasses:

ReferenceMapping, SubclassPCMapping

public abstract class MultiMapping
extends JavaTypeMapping

Mapping to represent multiple mappings within the single overall java type mapping. This mapping can be used to represent, for example,

• a reference field (where there are multiple implementations - of Object or interface)
• an element in a collection and the element has no table of its own, but multiple subclasses
• a FK of a PC field (where there may be multiple fields in the PK of the PC object)

Field Summary

protected JavaTypeMapping[]	javaTypeMappings The Java mappings represented by this mapping.
protected int	numberOfDatastoreMappings Number of datastore mappings - for convenience to improve performance

Fields inherited from class org.datanucleus.store.mapped.mapping.JavaTypeMapping

datastoreContainer, datastoreMappings, LOCALISER, mmd, referenceMapping, roleForMember, storeMgr, type

Constructor Summary

MultiMapping()

Method Summary

void	addJavaTypeMapping(JavaTypeMapping mapping) Method to add a Java type mapping for a field
DatastoreMapping	getDatastoreMapping(int index) Accessor for a datastore mapping.
DatastoreMapping[]	getDatastoreMappings() Accessor for the datastore mappings for this java type
JavaTypeMapping[]	getJavaTypeMapping() Accessor for the Java type mappings
int	getMappingNumberForValue(ObjectManager om, java.lang.Object value) Convenience accessor for the number of the java type mapping where the passed value would be stored.
int	getNumberOfDatastoreMappings() Accessor for the number of datastore mappings.
java.lang.Object	getObject(ObjectManager om, java.lang.Object rs, int[] pos) Method to retrieve an object of this type from the ResultSet.
void	setObject(ObjectManager om, java.lang.Object ps, int[] pos, java.lang.Object value) Method to set the parameters in the PreparedStatement with the fields of this object.
void	setObject(ObjectManager om, java.lang.Object ps, int[] pos, java.lang.Object value, StateManager ownerSM, int ownerFieldNumber) Sets the specified positions in the PreparedStatement associated with this field, and value.

Methods inherited from class org.datanucleus.store.mapped.mapping.JavaTypeMapping

addDatastoreMapping, equals, failureMessage, getBoolean, getByte, getChar, getColumnMetaDataForMember, getDatastoreContainer, getDouble, getFloat, getInt, getJavaType, getJavaTypeForDatastoreMapping, getLong, getMemberMetaData, getObject, getReferenceMapping, getRoleForMember, getSampleValue, getShort, getString, getType, getValueForDatastoreMapping, hashCode, hasSimpleDatastoreRepresentation, includeInFetchStatement, includeInInsertStatement, includeInUpdateStatement, initialize, initialize, isNullable, isSerialised, newLiteral, newScalarExpression, setBoolean, setByte, setChar, setDatastoreContainer, setDefault, setDouble, setFloat, setInt, setLong, setMemberMetaData, setReferenceMapping, setRoleForMember, setShort, setString

Methods inherited from class java.lang.Object

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

Field Detail

javaTypeMappings

protected JavaTypeMapping[] javaTypeMappings

The Java mappings represented by this mapping.

numberOfDatastoreMappings

protected int numberOfDatastoreMappings

Number of datastore mappings - for convenience to improve performance

Constructor Detail

MultiMapping

public MultiMapping()

Method Detail

addJavaTypeMapping

public void addJavaTypeMapping(JavaTypeMapping mapping)

Method to add a Java type mapping for a field

Parameters:

mapping - The mapping to add

getJavaTypeMapping

public JavaTypeMapping[] getJavaTypeMapping()

Accessor for the Java type mappings

Returns:

The Java type mappings

getNumberOfDatastoreMappings

public int getNumberOfDatastoreMappings()

Accessor for the number of datastore mappings.

Overrides:

getNumberOfDatastoreMappings in class JavaTypeMapping

Returns:

The number of datastore mappings.

getDatastoreMappings

public DatastoreMapping[] getDatastoreMappings()

Description copied from class: JavaTypeMapping

Accessor for the datastore mappings for this java type

Overrides:

getDatastoreMappings in class JavaTypeMapping

Returns:

The datastore mapping(s)

getDatastoreMapping

public DatastoreMapping getDatastoreMapping(int index)

Accessor for a datastore mapping.

Overrides:

getDatastoreMapping in class JavaTypeMapping

Parameters:

index - The position of the mapping to return

Returns:

The datastore mapping

getMappingNumberForValue

public int getMappingNumberForValue(ObjectManager om,
                                    java.lang.Object value)

Convenience accessor for the number of the java type mapping where the passed value would be stored. If no suitable mapping is found will return -1. If is a persistent interface then will return -2 meaning persist against *any* mapping

Parameters:

om - ObjectManager

value - The value

Returns:

The index of javaTypeMappings to use (if any), or -1 (none), or -2 (any)

setObject

public void setObject(ObjectManager om,
                      java.lang.Object ps,
                      int[] pos,
                      java.lang.Object value)

Method to set the parameters in the PreparedStatement with the fields of this object.

Overrides:

setObject in class JavaTypeMapping

Parameters:

om - Object Manager

ps - The PreparedStatement

pos - The parameter positions

value - The object to populate the statement with

Throws:

NotYetFlushedException - Thrown if the object is not yet flushed to the datastore

setObject

public void setObject(ObjectManager om,
                      java.lang.Object ps,
                      int[] pos,
                      java.lang.Object value,
                      StateManager ownerSM,
                      int ownerFieldNumber)

Sets the specified positions in the PreparedStatement associated with this field, and value.

Overrides:

setObject in class JavaTypeMapping

Parameters:

om - the ObjectManager

ps - a datastore object that executes statements in the database

pos - The position(s) of the PreparedStatement to populate

value - the value stored in this field

ownerSM - the owner StateManager

ownerFieldNumber - the owner absolute field number

getObject

public java.lang.Object getObject(ObjectManager om,
                                  java.lang.Object rs,
                                  int[] pos)

Method to retrieve an object of this type from the ResultSet.

Overrides:

getObject in class JavaTypeMapping

Parameters:

om - Object Manager

rs - The ResultSet

pos - The parameter positions

Returns:

The object