This topic applies only to the IBM Business Automation Workflow Advanced configuration.

Replacement variables in process and activity descriptions

Edit online
Draft comment:
This topic only applies to BAW, and is located in the BAW repository. Last updated on 2025-03-13 12:15
When used in descriptions for processes and activities, replacement expressions can be used to represent context variables that will be fully resolved at run time.
The replacement variables in process and activity descriptions must match the following syntax: 
%[<variableName>]\[<partName>][\<xpath>]%

<variableName>

The name of the variable is optional in cases where a default message is defined. For example, the description of an invoke activity uses the invoke's input message as the default variable.

Table 1. A list of all the default messages that are defined for process entities
Entity Default Message
Process The input message of the process
Invoke activity The input message of the invoke.
Human task activity (embedded inline in the process) The input message of the human task.
Receive activity The message received
Pick (Receive choice) activity The message received
Reply activity The reply message

For a process instance description, the default variable is the actual input message that started the process. For processes with multiple creating activities, the replacement string must be applicable for all the different types of input messages. In addition, the process variables are not initialized when the process description is resolved, meaning that the input message of the process is the only source that can be used in the replacement strings.

<partName>

The part name of the expression can only be specified for interface typed variables.

<xpath>

Variables can contain XPath expressions. If an XPath expression contains a "%" sign, it must be escaped as specified by XML (using &#37;).

It is expected that XPath will point to objects of type String, or String List. In general, and object will be replaced by what the toString() method returns.

Example

A description can contain multiple replacement expressions. For example, the description of an activity can be 
Waiting for '%user\name%' to return '%book\title%'
Here, the replacement variables refer to the data object variables inside the process that are named book and user, so no part name is specified. The replacement variables just contain the variable name and the XPath expression, which select the top-level elements name and title. For example, the expression can be resolved during run time to:
Waiting for 'Anke' to return 'Computer Networks'