...

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The following table shows the behavior of XML serialization for the examplefollowing class containing an array:

{
	"aClass" : { "anArray" : ["A1", "A2", "A3"] };
}

<aClass>
    <anArray>A1</anArray>
    <anArray>A2</anArray>
    <anArray>A3</anArray>
</aClass>

<aClass>
    <anArray>A1</anArray>
    <anArray>A3</anArray>
</aClass>

<aClass xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance">
    <anArray>A1</anArray>
    <anArray xsi:nil="true"/>
    <anArray>A3</anArray>
</aClass>

<aClass>
</aClass>

<aClass>
</aClass>

<aClass>
</aClass>

<aClass xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance">
    <anArray xsi:nil="true"/>
    <anArray xsi:nil="true"/>
    <anArray xsi:nil="true"/>
</aClass>

<anotherClass>
    <anArray>A1</anArray>
	<anArray>A2</anArray>
	<anArray>A3</anArray>
</anotherClass>

<AClassType>
    <anArray>A1</anArray>
	<anArray>A2</anArray>
	<anArray>A3</anArray>
</AClassType>

<aClass>
    <anArray>A1</anArray>
    <anArray>A2</anArray>
    <anArray>A3</anArray>
</aClass>

Examples

The following example shows how to convert Suppose an XML data structure contains elements with attribute values (in the example below these are street and city ), and you want to convert them to with mixed content to an UML class.

Suppose the following XML data structure with two elements street and city is given:

<address id="myAddress4711">
	<street id="234">Lautengartenstr. 12<4711-1">13, Coal Street</street>
	<city id="34">Basel<4711-2">New York, NY 10017, USA</city>
</address>

The class diagram below illustrates how to map the content of the XML element street ("Lautengartenstr. 1213, Coal Street") and the value of its attribute id ("2344711-1") to the UML association end street:

Figure: Mapping XML Data Structures to UML Classes

Image Removed

a class structure:

Image Added

To map XML element street and its attribute id, you need a dedicated class as a container. In this example, this is class StreetElement. XML attribute id of The street element from the above XML example is mapped to the association end street. The association end name must be the same as the name of the XML element. The associated class StreetElement is only a container for the street element. The name of the class is not relevant for the mapping. The XML attribute id of the element street is mapped to the class attribute id of the UML class StreetElement via matching names. The content of the XML element street is mapped to the class attribute text_value, which has the stereotype <<XMLCharacters>>that has stereotype <<XMLCharacters>>. In this example this is text_value.
Class StreetElement must have stereotype <<XML>> and tagged value isMixed set to true because it contains the serialized attribute text_value (also see explanation of tagged value isMixed).

Containter StreetElement is associated to the main address class. The name of the association end (street) must match the name of the XML element. Associated class StreetElement is only a container for the street element and its name is not relevant for the mapping.

If the XML element contains attributes, which should not be mapped to UML class attributes, an association to a base type can be used. The following example shows this for the element city. The content of the element ("BaselNew York, NY 10017, USA") will be available in city (accessible as attribute of the instantiated class Address2Example1). As the id attribute cannot be mapped, it will be discarded when executing the operation xmlToClass().

Figure: Preventing the Mapping of XML Attributes

Image Removed

Below, find the complete class diagram used for mapping the XML document address.xml.

Figure: Example when Using Operation xmlToClass()

...

If an object of class Address2Example1 were was serialized back in a SOAP response, the SOAP message would read:

<address2Example1 xmlns:ns1="urn:Services.URLService.URLPort.DataItems" xsi:type="ns1:Address2Example1">
    <id xsi:type="xsd:string">34<>4711</id>
    <street xsi:type="ns1:StreetElement">
      	<id xsi:type="xsd:string">234<>4711-1</id>
      	<text_value xsi:type="xsd:string">Lautengartenstr. 12
     	<>13, Coal Street</text_value>
    </street>
    <city xsi:type="xsd:string">Basel<>New York, NY 10017, USA</city>
</address2Example1>

The same result could be obtained with the following class diagram.

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:

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Image Removed Image Added

With the three XML stereotypes, one has the You have the flexibility to map XML structures in different ways. You can define very compact class diagrams for simple XML structures, but you have also the possibility to map complex XML data structures graphically.