XML Composite Direct Collection Mapping

XML composite direct collection mappings map a Java collection of simple object attributes to XML attributes and text nodes. Use multiplicity settings to specify an element as a collection. The XML schema allows you to define minimum and maximum occurrences. You can use a composite direct collection XML mapping in the following scenarios:

Mapping to Multiple Text Nodes
Mapping to Multiple Attributes
Mapping to a Single Text Node With an XML Composite Direct Collection Mapping
Mapping to a Single Attribute With an XML Composite Direct Collection Mapping
Mapping to a List of Unions With an XML Composite Direct Collection Mapping
Mapping to a Union of Lists With an XML Composite Direct Collection Mapping
Specifying the Content Type of a Collection With an XML Composite Direct Collection Mapping

See Chapter 68, "Configuring an XML Composite Direct Collection Mapping" for more information.

Mapping to Multiple Text Nodes

This section describes using a composite direct collection XML mapping when:

Mapping to a Simple Sequence
Mapping to a Sequence in a Subelement

Mapping to a Simple Sequence

Given the XML schema in Example 65-24, Figure 65-15 illustrates a composite direct collection XML mapping to a simple sequence of text nodes in a corresponding XML document. Example 65-25 shows how to configure this mapping in Java.

Example 65-24 Schema for Composite Direct Collection XML Mapping to a Simple Sequence

<?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="task" type="xsd:string" maxOccurs="unbounded"/>
        </xsd:sequence>
    </xsd:complexType>
</xsd:schema>

Figure 65-15 Composite Direct Collection XML Mapping to a Simple Sequence

This illustaration is described in the preceeding paragraph.

Example 65-25 Java for Composite Direct Collection XML Mapping to a Simple Sequence

XMLCompositeDirectCollectionMapping tasksMapping = new XMLCompositeDirectCollectionMapping();
tasksMapping.setAttributeName("tasks");
tasksMapping.setXPath("task/text()");

Mapping to a Sequence in a Subelement

Given the XML schema in Example 65-26, Figure 65-16 illustrates a composite direct collection XML mapping to a sequence of text nodes in a subelement in a corresponding XML document. Example 65-27 shows how to configure this mapping in Java.

Example 65-26 Schema for Composite Direct Collection XML Mapping to a Subelement Sequence

<?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">
                <xsd:complexType>
                    <xsd:sequence>
                        <xsd:element name="task" type="xsd:string" maxOccurs="unbounded"/>
                    </xsd:sequence>
                </xsd:complexType>
            </xsd:element>
        </xsd:sequence>
    </xsd:complexType>
</xsd:schema>

Figure 65-16 Composite Direct Collection XML Mapping to a Subelement Sequence

Example 65-27 Java for Composite Direct Collection XML Mapping to a Subelement Sequence

XMLCompositeDirectCollectionMapping tasksMapping = new XMLCompositeDirectCollectionMapping();
tasksMapping.setAttributeName("tasks");
tasksMapping.setXPath("tasks/task/text()");

Mapping to Multiple Attributes

Given the XML schema in Example 65-28, Figure 65-17 illustrates a composite direct collection XML mapping to a sequence of text nodes in a subelement in a corresponding XML document. Example 65-29 shows how to configure this mapping in Java.

Example 65-28 Schema for Composite Direct Collection XML Mapping to Multiple Attributes

<?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" maxOccurs="unbounded">
                <xsd:complexType>
                    <xsd:attribute name="task" type="xsd:string"/>
                </xsd:complexType>
            </xsd:element>
        </xsd:sequence>
    </xsd:complexType>
</xsd:schema>

Figure 65-17 Composite Direct Collection XML Mapping to Multiple Attributes

Example 65-29 Java for Composite Direct Collection XML Mapping to Multiple Attributes

XMLCompositeDirectCollectionMapping tasksMapping = new XMLCompositeDirectCollectionMapping();
tasksMapping.setAttributeName("tasks/@task");
tasksMapping.setXPath("task/text()");

Mapping to a Single Text Node With an XML Composite Direct Collection Mapping

When you map a collection to a single node, the contents of the node is treated as a space-separated list.

Given the XML schema in Example 65-30, Figure 65-18 illustrates a composite direct collection XML mapping to a single text node in a corresponding XML document. Example 65-31 shows how to configure this mapping in Java.

Example 65-30 Schema for XML Composite Direct Collection Mapping to a Single Text Node

<?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>

Figure 65-18 XML Composite Direct Collection Mapping to a Single Text Node

Description of "Figure 65-18 XML Composite Direct Collection Mapping to a Single Text Node"

Example 65-31 Java for XML Composite Direct Collection Mapping to a Single Text Node

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

Mapping to a Single Attribute With an XML Composite Direct Collection Mapping

Given the XML schema in Example 65-32, Figure 65-19 illustrates a composite direct collection XML mapping to a single attribute in a corresponding XML document. Example 65-33 shows how to configure this mapping in Java.

Example 65-32 Schema for XML Composite Direct Collection Mapping to a Single Attribute

<?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:attribute name="tasks" type="tasks-type"/>
    </xsd:complexType>
    <xsd:simpleType name="tasks-type">
        <xsd:list itemType="xsd:string"/>
    </xsd:simpleType>
</xsd:schema>

Figure 65-19 XML Composite Direct Collection Mapping to a Single Attribute

Example 65-33 Java for XML Composite Direct Collection Mapping to a Single Attribute

XMLCompositeDirectCollectionMapping tasksMapping = new XMLCompositeDirectCollectionMapping();
tasksMapping.setAttributeName("tasks");
tasksMapping.setXPath("@tasks");
tasksMapping.setUsesSingleNode(true);

Mapping to a List of Unions With an XML Composite Direct Collection Mapping

Given the XML schema in Example 65-34, Figure 65-20 illustrates a composite direct collection XML mapping to a list of unions in a corresponding XML document. Example 65-35 shows how to configure this mapping in Java.

Example 65-34 Schema for XML Composite Direct Collection Mapping to List of Unions

<?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>

Figure 65-20 Composite XML Direct Collection Mapping to List of Unions

Description of "Figure 65-20 Composite XML Direct Collection Mapping to List of Unions"

Example 65-35 Java for XML Composite Direct Collection Mapping to List of Unions

XMLCompositeDirectCollectionMapping mapping = new XMLCompositeDirectCollectionMapping();
mapping.setAttributeName("myattribute");
XMLUnionField field = new XMLUnionField("listOfUnions/text()");
mapping.addSchemaType(new Qname(url,"int"));
mapping.addSchemaType(new Qname(url,"date"));
mapping.setField(field);
mapping.useSingleElement(false);

Mapping to a Union of Lists With an XML Composite Direct Collection Mapping

Given the XML schema in Example 65-34, Figure 65-20 illustrates an XML composite direct collection mapping to a list of unions in a corresponding XML document. Example 65-35 shows how to configure this mapping in Java.

Example 65-36 Schema for XML Composite Direct Collection Mapping to a Union of Lists

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

Figure 65-21 XML Composite Direct Collection Mapping to a Union of Lists

Description of "Figure 65-21 XML Composite Direct Collection Mapping to a Union of Lists"

Note that in this example, valid XML documents contain either all xsd:double, all xsd:date, or all xsd:integer values.

Example 65-37 Java for XML Composite Direct Collection Mapping to a Union of Lists

XMLCompositeDirectCollectionMapping mapping = new XMLCompositeDirectCollectionMapping();
mapping.setAttributeName("myattribute");
mapping.useSingleElement(false);
XMLUnionField unionField = new XMLUnionField("UnionOfLists/text()");
field.addSchemaType(new Qname(url," integer"))
field.addSchemaType (new Qname(url," date"))
field.addSchemaType (new Qname(url," double"))
field.setUsesSingleNode(false);

Specifying the Content Type of a Collection With an XML Composite Direct Collection Mapping

By default, TopLink will treat the node values read 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.

Given the XML schema in Example 65-38, Figure 65-22 illustrates an XML composite direct collection mapping to a simple sequence in a corresponding XML document. The mapping is configured to specify the content type of the collection as Calendar. Example 65-39 shows how to configure this mapping in Java.

Example 65-38 Schema for XML Composite Direct Collection Mapping with Specified Content Type

<?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>

Figure 65-22 XML Composite Direct Collection Mapping with Specified Content Type

Description of "Figure 65-22 XML Composite Direct Collection Mapping with Specified Content Type"

Example 65-39 Java for XML Composite Direct Collection Mapping with Specified Content Type

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