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Oracle Fusion Middleware Java API Reference for Oracle TopLink 11g Release 1 (11.1.1) B32476-03 |
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java.lang.Object oracle.toplink.mappings.DatabaseMapping oracle.toplink.mappings.foundation.AbstractCompositeDirectCollectionMapping oracle.toplink.ox.mappings.XMLCompositeDirectCollectionMapping
public class XMLCompositeDirectCollectionMapping
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:
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 |
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@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.
Constructor Summary | |
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XMLCompositeDirectCollectionMapping()
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Method Summary | |
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java.lang.String |
getXPath()
Get the XPath String |
boolean |
isCDATA()
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void |
setIsCDATA(boolean CDATA)
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void |
setXPath(java.lang.String xpathString)
Set the Mapping field name attribute to the given XPath String |
void |
useCollectionClassName(java.lang.String concreteContainerClassName)
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Methods inherited from class oracle.toplink.mappings.foundation.AbstractCompositeDirectCollectionMapping |
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getAttributeElementClass, getFieldElementClass, getFieldName, getValueConverter, hasValueConverter, setAttributeElementClass, setContainerPolicy, setField, setFieldElementClass, setUsesSingleNode, setValueConverter, simpleAddToCollectionChangeRecord, simpleRemoveFromCollectionChangeRecord, useCollectionClass, useMapClass, usesSingleNode |
Methods inherited from class oracle.toplink.mappings.DatabaseMapping |
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getAttributeAccessor, getAttributeClassification, getAttributeName, getGetMethodName, getProperty, getReferenceDescriptor, getSetMethodName, isLazy, isOptional, isUsingMethodAccess, readOnly, readWrite, setAttributeAccessor, setAttributeName, setGetMethodName, setIsLazy, setIsOptional, setIsReadOnly, setProperty, setSetMethodName, setWeight |
Methods inherited from class java.lang.Object |
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equals, getClass, hashCode, notify, notifyAll, wait, wait, wait |
Constructor Detail |
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public XMLCompositeDirectCollectionMapping()
Method Detail |
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public void setXPath(java.lang.String xpathString)
xpathString
- Stringpublic java.lang.String getXPath()
public void useCollectionClassName(java.lang.String concreteContainerClassName)
public void setIsCDATA(boolean CDATA)
public boolean isCDATA()
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