WebSphere Message Broker, Version 8.0.0.7
Operating Systems: AIX, HP-Itanium, Linux, Solaris, Windows, z/OS
See information about the latest product version
See information about the latest product version
Transforming pattern parameters
Calculate a pattern parameter value from the values entered for other pattern parameters.
Before you start:
Complete the following tasks:You can transform pattern parameters by using XPath expressions;
for example, to calculate a pattern parameter value from the values
entered for other pattern parameters. WebSphere® Message
Broker supports XPath 1.0. For XPath
reference information, including information about XPath functions,
see W3C XPath 1.0 Specification.
- The pp:getValue() function is included, in addition
to the functions in the XPath 1.0 Specification. The pp:getValue() function
takes the parameter ID of a pattern parameter and returns the value
of that pattern parameter. To see the parameter ID for a pattern parameter:
- In the Pattern Configuration tab of the Pattern Authoring editor, double-click a parameter, or select a parameter and click Edit. The Edit Parameter window opens.
- Click the Transform tab. The parameter IDs for pattern parameters are shown in the Parameter ID column of the Pattern Parameters table.
- When a pattern instance is generated by a pattern user, transformation
expressions are processed before any Java™ and
PHP code that has been added to modify pattern instances. Transformation
of pattern parameters is processed in the following sequence:
- Every parameter that has an XPath transformation expression is evaluated.
- The value of each parameter that has an XPath transformation expression is updated with the result of its evaluation, overwriting the value entered by the pattern user.
- The parameters are evaluated in top to bottom order, as they are listed in the Pattern Configuration tab of the Pattern Authoring editor.
To transform a pattern parameter by using an XPath expression: