exists
Use
Use this function to determine whether a particular source field exists in the XML instance to be processed. If it does,
exists() returns the value true, otherwise it returns the value false.Example
In the example below, a function description is to be mapped to a structure that merely comprises the technical name and the description of the function. The source structure field
description is optional, however, the target structure field descriptionOfUse is mandatory (minOccurs = 1).Source Structure (left) and Target Structure (right)
|
Field Name |
minOccurs |
maxOccurs |
Field Name |
min- |
max- |
|
FunctionDeclMsg |
1 |
1 |
FunctionHeadingMsg |
1 |
1 |
|
name |
1 |
1 |
technicalName |
1 |
1 |
|
description |
0 |
1 |
descriptionOfUse |
1 |
1 |
|
inputArg |
0 |
64 |
|||
|
name (Attr) |
1 |
1 |
|||
|
type (Attr) |
1 |
1 |
|||
|
returnValue |
0 |
1 |
|||
|
type (Attr) |
1 |
1 |
Using the
exists()function and other Boolean functions you can output a specified string by default if the description-tag does not exist here. This ensures that the target field descriptionOfUse is always completed and is never empty.Message Mapping Using exists()
|
Target Field Mapping |
Value of Constant() |
|
/FunctionHeadingMsg=/FunctionDeclMsg |
|
|
/FunctionHeadingMsg/technicalName=/FunctionDeclMsg/name |
|
|
/FunctionHeadingMsg/descriptionOfUse= |
(No description available) |
The text description of the
if standard function must be read as follows: if ( <result if condition true>,Example
|
Source Instance |
Result |
|
<?xml version="1.0"
<FunctionDeclMsg> <name> <inputArg <inputArg <inputArg <returnValue type="String" /> </FunctionDeclMsg> |
<?xml version="1.0"
<ns0:FunctionHeadingMsg <technicalName> <descriptionOfUse> </ns0:FunctionHeadingMsg> |