XML Null handling options

The XML wire format layer supports handling of null values within messages. NULL properties for XML are set for a message set only and apply to all the defined objects within the message set.

You can use the following two NULL encoding properties to represent the numeric and non-numeric encoding for NULL within the XML layer:

These represent the numeric and non numeric encoding for NULL within the XML layer:

Each of these encodings has five enumerated values:

The table below defines the XML options for encoding null values.

Encoding Null Num
Encoding Null Non-Num

Encoding Null Num Val
Encoding Null Non-Num Val

Example XML
NULLEmpty (default) not applicable <child></child>
NULLValue zzz <child>zzz</child>
NULLElement null <child><null/></child>
NULLValueAttribute not applicable
<child></child>2
<child id="X"></child>3
NULLXMLSchema null <child null='true'>1
Notes:
  1. The value of Boolean True is used.
  2. This is only valid for XMLElementAttrVal element rendering, as specified in XML Message rendering options. Marking an element as being rendered in this way, and setting it to null, is equivalent to removing the attribute of the element that detailed the element's value.
  3. This is only valid for XMLElementAttrIdVal element rendering, as specified in XML Message rendering options. Marking an element as being rendered in this way, and setting it to null, is equivalent to removing the attribute of the element that detailed the element's value, but not removing the attribute id.

You do not have to supply additional clarification for NULLEmpty and NULLValAttr, but if you select NULLValue, NULLAttribute, or NULLElement, you must define further values to be assigned to represent the NULL condition in the Encoding Null Num Value and Encoding Null Non-Num Value message set properties (see the table above).

Related concepts
Message modeling
The message model
Related tasks
Developing message models
Working with message model objects
Related reference
Message model reference information
Message model object properties
Additional MRM domain information
Additional XML information