You need a separate action for exception handling. This action is executed once an exception is recognized. For the purpose of the tutorial, you assign the User ID Input Form callable object to the action, so that the input form is called again to recover from the error.
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1. Open the gallery and choose Create Action from the contextual panel.
2. From the Original Language dropdown box, select English and choose Create.
The action’s design time opens.
3. Enter the required data as follows:
¡ Name – enter Handle: User ID Input Form
¡ Description – enter a brief description of the callable object; for example, Handle: User ID Input Form
¡ Location – choose the Exception Handling folder
4. Make sure that Callable Object for Execution is selected from the Item dropdown list, and choose (Insert).
5. Browse to select User ID Input Form.
To confirm, choose Select.
6. Choose (Activate).
Next, you have to do the following:
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1. Create an action for the background step. Insert the callable object for background execution that you have created in Exposing a Java Class as a Callable Object.
2. Create a Data Display Form.
More information: Creating a Data Display Form