Creating an external implementation to implement an activity

You can implement a user task to use applications outside of IBM® Business Automation Workflow (called external implementations), such as by modeling an activity that is implemented by a custom Eclipse RCP or Microsoft .NET application. You could also use a system task to call an external implementation; however, this use of system tasks is deprecated, so use a user task instead.

1. Open a process and click the activity that you want to implement using a custom application.
2.  V20.0.0.2  Click the General tab in the properties.
3. Under Implementation, select the User Task option from the displayed list.
4. Click the Select button to choose an external service from the library.
5. In the Task Header section, specify the following properties:

   Table 1. Properties in the Task Header section

   Property	Action
   Subject	Type a descriptive subject for the task that is generated in IBM Process Portal when you run the process. You can also use the IBM Business Automation Workflow embedded JavaScript syntax (for example, <#=tw.local.mySubject#>) to express the subject.
   Narrative	Type an optional description. You can also use the Business Automation Workflow embedded JavaScript syntax to express the narrative. Restriction: Do not use JavaScript variable references in task narratives if you need the data to be available after the task completes. Once a task is complete, Business Automation Workflow removes the data for completed tasks to conserve space. Instead, store the data items in another location, such as a database.

   Note: For the following properties (in the Priority Settings section) you can click the JS button for an option if you prefer to use a JavaScript expression with predefined variables to establish the priority settings.
6. For the Priority field, select one of the default priority codes: Very Urgent, Urgent, Normal, Low, or Very Low. You can also use a JavaScript expression with predefined variables to establish the priority settings.
7. Enter the Due In date in one of the following ways:
   • Enter a value in the text box and then choose Minutes, Hours, or Days.

     Do not set a due in value greater than 800 Hours, Minutes, or Days as it decreases performance. Instead, use a JavaScript expression to directly set the due date.

   • Enter JavaScript. You must return a TWDate object
   • Select an existing variable from the library. At run time, the variable should reflect the value that you want for the time period. Be sure to select the option that you want from the drop-down list: Minutes, Hours, or Days.
8. For the Time Zone field, select the time zone that you want to apply to the tasks that result from the current activity. For example, you can select US/Pacific for users who work in California.
9. For the Holiday Schedule field, you can leave the setting at (use default) as described in the preceding note or you can click the JS button if you prefer to use a JavaScript expression. Each Holiday Schedule is made up of a list of Dates.

   You can leave the Time Schedule, Timezone, and Holiday Schedule fields set to (use default). If you do, the work schedule specified for the process used. See Setting the work schedule for a process for more information.

   If you choose JavaScript, you can enter either a String (or String-generated JavaScript) or JavaScript that returns a TWHolidaySchedule variable. If you use a String, then Business Automation Workflow looks up the holiday schedule by name according to those rules. If you use a TWHolidaySchedule variable, then Business Automation Workflow assumes that the holiday schedule is filled in appropriately. (Go to the System Data toolkit and open the TWHolidaySchedule variable to view its parameters.)

10. Click the Data Mapping tab in the properties.

    Because you added the input and output parameters for the external implementation when you created it, the Data Mapping tab for the activity in the process should include those parameters.

    Under Input Mapping, click the auto-map icon in the upper-right corner, and then click the auto-map icon in the upper-right corner of the Output Mapping section. For more information about mapping variables, see Business objects and variables in Process Designer.

11. Click Save or Finish Editing.