org.eclipse.persistence.oxm.mappings
Class XMLCompositeDirectCollectionMapping

java.lang.Object
  org.eclipse.persistence.mappings.DatabaseMapping
      org.eclipse.persistence.mappings.foundation.AbstractCompositeDirectCollectionMapping
          org.eclipse.persistence.oxm.mappings.XMLCompositeDirectCollectionMapping

All Implemented Interfaces:

java.io.Serializable, java.lang.Cloneable, ContainerMapping, XMLMapping

Direct Known Subclasses:

XMLBinaryDataCollectionMapping

public class XMLCompositeDirectCollectionMapping
extends AbstractCompositeDirectCollectionMapping
implements XMLMapping

Composite direct collection XML mappings map a collection of simple types (String, Number, Date, etc.) to and from a sequence of composite XML nodes.

Composite direct collection XML mappings can be used in the following scenarios:

• Mapping to Multiple Text Nodes
• Mapping to Multiple Attributes
• Mapping to a Single Text Node
• Mapping to a Single Attribute
• Mapping to a List of Unions
• Mapping a Union of Lists
• Specifying the Content Type of a Collection

Setting the XPath: TopLink XML mappings make use of an XPath statement to find the relevant data in an XML document. The XPath statement is relative to the context node specified in the descriptor. The XPath may contain node type, path, and positional information. The XPath is specified on the mapping using the setXPath method.

The following XPath statements may be used to specify the location of XML data relating to an object's name attribute:

XPath	Description
@tasks	The "@" character indicates that the node is an attribute. This XPath applies only to the single attribute node case; each member of the collection is mapped to a single node.
tasks/@task	The "@" character indicates that the node is an attribute. The information is stored in the attribute node of the tasks element.
text()	"text()" indicates that the node is a text node. In this case the task value in the text node belongs to the context node.
tasks/text()	The task information is stored in the text node of the tasks element.
tasks/task/text()	The XPath statement may be used to specify any valid path.
task[2]/text()	The XPath statement may contain positional information. In this case the task information is stored in the text node of the second occurrence of the task element.

Mapping to a Single Text Node: By default, TopLink maps each member of a collection to it's own node. It is possible, however, to mapping a collection to a single node; here the contents of the node is treated as a space-separated list. This behavior is set on the mapping using the setUsesSingleNode method, with 'true' as the parameter.

XML Schema
<?xml version="1.0" encoding="UTF-8"?>
<xsd:schema xmlns:xsd="http://www.w3.org/2001/XMLSchema">
<xsd:element name="employee" type="employee-type"/>
<xsd:complexType name="employee-type">
<xsd:sequence>
<xsd:element name="tasks" type="tasks-type"/>
</xsd:sequence>
</xsd:complexType>
<xsd:simpleType name="tasks-type">
<xsd:list itemType="xsd:string"/>
</xsd:simpleType>
</xsd:schema>


Code Sample
XMLCompositeDirectCollectionMapping tasksMapping = new XMLCompositeDirectCollectionMapping();
tasksMapping.setAttributeName("tasks");
tasksMapping.setXPath("tasks/text()");
tasksMapping.setUsesSingleNode(true);


Specifying the Content Type of a Collection: By default, TopLink will treat the node values read in by a composite direct collection XML mapping as objects of type String. You can override this behavior by specifying the type of the collection's contents.

XML Schema
<?xml version="1.0" encoding="UTF-8"?>
<xsd:schema xmlns:xsd="http://www.w3.org/2001/XMLSchema">
<xsd:element name="employee" type="employee-type"/>
<xsd:complexType name="employee-type">
<xsd:sequence>
<xsd:element name="vacation" type="xsd:string" maxOccurs="unbounded"/>
</xsd:sequence>
</xsd:complexType>
</xsd:schema>


Code Sample
XMLCompositeDirectCollectionMapping tasksMapping = new XMLCompositeDirectCollectionMapping();
tasksMapping.setAttributeName("vacationDays");
tasksMapping.setXPath("vacation/text()");
tasksMapping.setAttributeElementClass(Calendar.class);


Mapping to a List of Unions:

XML Schema
<?xml version="1.0" encoding="UTF-8"?>
<xsd:schema xmlns:xsd="http://www.w3.org/2001/XMLSchema">
<xsd:element name="vacation" type="listOfUnions"/>
<xsd:simpleType name="listOfUnions">
<xsd:list>
<xsd:simpleType>
<xsd:union memberTypes="xsd:date xsd:integer"/>
</xsd:simpleType>
</xsd:list>
</xsd:simpleType>
</xsd:schema>


Code Sample
XMLCompositeDirectCollectionMapping mapping = new XMLCompositeDirectCollectionMapping();
mapping.setAttributeName("myattribute");
XMLUnionField field = new XMLUnionField("listOfUnions/text()");
mapping.addSchemaType(new QName(url,XMLConstants.INT));
mapping.addSchemaType(new QName(url,XMLConstants.DATE));
mapping.setField(field);
mapping.useSingleElement(false);


More Information: For more information about using the XML Composite Direct Collection Mapping, see the "Understanding XML Mappings" chapter of the Oracle TopLink Developer's Guide.

See Also:

Serialized Form

Since:

Oracle TopLink 10g Release 2 (10.1.3)

Field Summary

Fields inherited from class org.eclipse.persistence.mappings.foundation.AbstractCompositeDirectCollectionMapping

elementDataTypeName, field, valueConverter

Fields inherited from class org.eclipse.persistence.mappings.DatabaseMapping

attributeAccessor, attributeName, descriptor, fields, isLazy, isOptional, isPrimaryKeyMapping, isReadOnly, isRemotelyInitialized, NO_FIELDS, NO_WEIGHT, properties, weight, WEIGHT_1

Constructor Summary

XMLCompositeDirectCollectionMapping()

Method Summary

java.lang.String	getXPath() Get the XPath String
void	initialize(org.eclipse.persistence.internal.sessions.AbstractSession session) INTERNAL: Initialize the mapping.
boolean	isCDATA()
boolean	isXMLMapping() INTERNAL:
void	setIsCDATA(boolean CDATA)
void	setXPath(java.lang.String xpathString) Set the Mapping field name attribute to the given XPath String
void	useCollectionClassName(java.lang.String concreteContainerClassName)
java.lang.Object	valueFromRow(org.eclipse.persistence.internal.sessions.AbstractRecord row, org.eclipse.persistence.internal.queries.JoinedAttributeManager joinManager, ObjectBuildingQuery sourceQuery, org.eclipse.persistence.internal.sessions.AbstractSession executionSession) INTERNAL: Build the nested collection from the database row.
void	writeFromObjectIntoRow(java.lang.Object object, org.eclipse.persistence.internal.sessions.AbstractRecord row, org.eclipse.persistence.internal.sessions.AbstractSession session) INTERNAL:
void	writeSingleValue(java.lang.Object value, java.lang.Object parent, XMLRecord record, org.eclipse.persistence.internal.sessions.AbstractSession session) INTERNAL: A method that marshals a single value to the provided Record based on this mapping's XPath.

Methods inherited from class org.eclipse.persistence.mappings.foundation.AbstractCompositeDirectCollectionMapping

buildAddedElementFromChangeSet, buildBackupClone, buildChangeSet, buildClone, buildCloneFromRow, buildClonePart, buildCopy, buildElementFromChangeSet, buildElementFromElement, buildRemovedElementFromChangeSet, cascadePerformRemoveIfRequired, cascadeRegisterNewIfRequired, collectFields, compareElements, compareElementsForChange, compareForChange, compareObjects, convertToChangeRecord, fixObjectReferences, getAttributeElementClass, getContainerPolicy, getField, getFieldClassification, getFieldElementClass, getFieldName, getRealCollectionAttributeValueFromObject, getValueConverter, hasValueConverter, isAbstractCompositeDirectCollectionMapping, iterate, mapKeyHasChanged, mergeChangesIntoObject, mergeIntoObject, setAttributeElementClass, setContainerPolicy, setField, setFieldElementClass, setUsesSingleNode, setValueConverter, simpleAddToCollectionChangeRecord, simpleRemoveFromCollectionChangeRecord, useCollectionClass, useMapClass, usesSingleNode, writeFromObjectIntoRowForUpdate, writeFromObjectIntoRowWithChangeRecord, writeInsertFieldsIntoRow

Methods inherited from class org.eclipse.persistence.mappings.DatabaseMapping

addToCollectionChangeRecord, buildBackupCloneForPartObject, buildChangeRecord, buildCloneForPartObject, buildExpression, buildObjectJoinExpression, buildObjectJoinExpression, buildShallowOriginalFromRow, calculateDeferredChanges, cascadeDiscoverAndPersistUnregisteredNewObjects, cascadeMerge, cascadePerformRemovePrivateOwnedObjectFromChangeSetIfRequired, clone, cloneFields, convertClassNamesToClasses, createUnitOfWorkValueHolder, extractNestedExpressions, fixRealObjectReferences, getAttributeAccessor, getAttributeClassification, getAttributeName, getAttributeValueFromObject, getDescriptor, getFields, getGetMethodName, getObjectCorrespondingTo, getProperties, getProperty, getRealAttributeValueFromAttribute, getRealAttributeValueFromObject, getReferenceDescriptor, getRelationshipPartner, getSelectFields, getSelectTables, getSetMethodName, getValueFromRemoteValueHolder, getWeight, hasConstraintDependency, hasDependency, hasInverseConstraintDependency, hasRootExpressionThatShouldUseOuterJoin, instantiateAttribute, isAbstractCompositeCollectionMapping, isAbstractCompositeObjectMapping, isAbstractDirectMapping, isAggregateCollectionMapping, isAggregateMapping, isAggregateObjectMapping, isCandidateForPrivateOwnedRemoval, isCascadedLockingSupported, isChangeTrackingSupported, isCloningRequired, isCollectionMapping, isDatabaseMapping, isDirectCollectionMapping, isDirectMapMapping, isDirectToFieldMapping, isDirectToXMLTypeMapping, isEISMapping, isForeignReferenceMapping, isJoiningSupported, isLazy, isManyToManyMapping, isNestedTableMapping, isObjectReferenceMapping, isOneToManyMapping, isOneToOneMapping, isOptional, isPrimaryKeyMapping, isPrivateOwned, isReadOnly, isReferenceMapping, isRelationalMapping, isRemotelyInitialized, isStructureMapping, isTransformationMapping, isUnidirectionalOneToManyMapping, isUsingMethodAccess, isVariableOneToOneMapping, isWriteOnly, iterateOnRealAttributeValue, performDataModificationEvent, postCalculateChanges, postCalculateChangesOnDeleted, postDelete, postInitialize, postInsert, postUpdate, preDelete, preInitialize, preInsert, prepareCascadeLockingPolicy, preUpdate, readFromResultSetIntoObject, readFromRowIntoObject, readOnly, readWrite, rehashFieldDependancies, remoteInitialization, remotelyInitialized, removeFromCollectionChangeRecord, replaceValueHoldersIn, setAttributeAccessor, setAttributeName, setAttributeValueInObject, setChangeListener, setDescriptor, setFields, setGetMethodName, setIsLazy, setIsOptional, setIsPrimaryKeyMapping, setIsReadOnly, setProperties, setProperty, setRealAttributeValueInObject, setSetMethodName, setWeight, toString, updateChangeRecord, updateCollectionChangeRecord, validateAfterInitialization, validateBeforeInitialization, valueFromObject, valueFromResultSet, valueFromRow, verifyDelete, writeFromAttributeIntoRow, writeFromObjectIntoRowForShallowInsert, writeFromObjectIntoRowForShallowInsertWithChangeRecord, writeFromObjectIntoRowForWhereClause, writeUpdateFieldsIntoRow

Methods inherited from class java.lang.Object

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

Constructor Detail

XMLCompositeDirectCollectionMapping

public XMLCompositeDirectCollectionMapping()

Method Detail

isXMLMapping

public boolean isXMLMapping()

INTERNAL:

Overrides:

isXMLMapping in class DatabaseMapping

initialize

public void initialize(org.eclipse.persistence.internal.sessions.AbstractSession session)
                throws DescriptorException

INTERNAL: Initialize the mapping.

Overrides:

initialize in class AbstractCompositeDirectCollectionMapping

Throws:

DescriptorException

setXPath

public void setXPath(java.lang.String xpathString)

Set the Mapping field name attribute to the given XPath String

Parameters:

xpathString - String

getXPath

public java.lang.String getXPath()

Get the XPath String

Returns:

String the XPath String associated with this Mapping

useCollectionClassName

public void useCollectionClassName(java.lang.String concreteContainerClassName)

valueFromRow

public java.lang.Object valueFromRow(org.eclipse.persistence.internal.sessions.AbstractRecord row,
                                     org.eclipse.persistence.internal.queries.JoinedAttributeManager joinManager,
                                     ObjectBuildingQuery sourceQuery,
                                     org.eclipse.persistence.internal.sessions.AbstractSession executionSession)
                              throws DatabaseException

INTERNAL: Build the nested collection from the database row.

Overrides:

valueFromRow in class AbstractCompositeDirectCollectionMapping

Throws:

DatabaseException

writeFromObjectIntoRow

public void writeFromObjectIntoRow(java.lang.Object object,
                                   org.eclipse.persistence.internal.sessions.AbstractRecord row,
                                   org.eclipse.persistence.internal.sessions.AbstractSession session)

INTERNAL:

Overrides:

writeFromObjectIntoRow in class AbstractCompositeDirectCollectionMapping

writeSingleValue

public void writeSingleValue(java.lang.Object value,
                             java.lang.Object parent,
                             XMLRecord record,
                             org.eclipse.persistence.internal.sessions.AbstractSession session)

Description copied from interface: XMLMapping

INTERNAL: A method that marshals a single value to the provided Record based on this mapping's XPath. Used for Sequenced marshalling.

Specified by:

writeSingleValue in interface XMLMapping

Parameters:

value - - The value to be marshalled

record - - The Record the value is being marshalled too.

setIsCDATA

public void setIsCDATA(boolean CDATA)

isCDATA

public boolean isCDATA()