Checking for pattern errors

You can apply a pattern you have designed in a runtime instance of the developer workbench to test for errors. Errors are reported back to the Console view of the developer workbench.

This topic discusses some basic steps to follow when you are debugging a pattern by using the both the developer and runtime workbenches. It assumes that you have both a developer and a runtime instance of the workbench running.
Note: You cannot change the pattern code in the developer workbench while the run time workbench is running.

Before you test a pattern, you can add debug messages to the hot spots to trace the process sequence for expansion and update methods. Trace messages are displayed in the developer workbench Console view. The pattern cheat sheet, Authoring Patterns, provides detailed examples of how add debug messages. You open the cheat sheets from the Help menu.

If you included breakpoints in your pattern code; they are listed and controlled in the Breakpoint view in the developer workbench. You can resume pattern processing after a reaching a breakpoint by clicking Run > Resume.

For details on applying patterns, refer to the topics on applying patterns. As every pattern is unique, there is no single method to test patterns. The following instructions are options to modify the pattern. Parameters with dependencies invoke multiple methods for each command when a change occurs to a supplier parameter.

To test your pattern, do one or more of the following steps:
  1. Add an argument to each template parameter by using the Apply pattern wizard or drag and drop gestures. The expansion method that handles added values are invoked.
  2. Delete each argument by using the Undo or Delete from Model menu items. The expansion method that handles removed values is invoked.
  3. Replace an argument with another. This action invokes an method for handling removed values and then a method for handling added values.
  4. Reapply the pattern to reevaluate all arguments bound to the pattern instance. Reapplying a pattern updates any arguments that were bound and then modified outside of the pattern.
  5. Unapply the pattern to invoke a remove of all arguments. This action removes the pattern.
  6. Unbind a single argument to invoke a remove method. The expansion method for handling removed values is invoked.
After you have satisfactorily tested all patterns in a library, package the pattern library as a RAS pattern asset. To do this, you export it by using the Pattern Authoring view. As a RAS pattern asset, patterns are easily distributed for use by other developers. When imported, the RAS pattern asset is installed as a pattern plug-in and is listed in the Pattern Explorer view and the Pattern Repository or the RAS Asset Explorer view.

Parent topic: Testing patterns
Previous topic: Starting a run time debug workbench

Related concepts
IBM Rational design patterns
Pattern code and support files
Pattern instantiations

Related information
Displaying available patterns

Creating pattern instances

Specifying arguments for pattern instances

Exporting RAS assets

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