Comparator provides an extension that can be used to extend, enhance, or replace the standard comparison of expected output.

Each test suite can have its comparator that can be specified from the user interface.

"Custom" comparator type are Java classes that implement the com.wm.ps.test.ResultsValidator interface. This also provides a mechanism to execute operations pre and post service execution.

The "Custom Service" comparator type allows you to select an Integration Server service that has an assertion logic for the test. The service signature must conform to the wm.spec:result_comparator specification.

Using "Custom" and "Custom Service" comparator types, you can build some basic functional testing capability. For example, if a service writes to a database table, a comparator can compare the results from the service and check the destination table to confirm the operation executed successfully. You can also specify filters while comparing.