You will need to write a Java class that has methods that can be called to retrieve information. The example in the following section, Defining a Hidden Form Field, uses the getJobGrade method, which is a custom method. You should locate this custom class in the idm\WEB-INF\classes\com\waveset\custom directory structure. (If these directories do not exist on your system, you must create them.)
Follow these guidelines when writing this class:
If the method performs an expensive operation, such as a database request, you should make the call in the Default expression of a hidden form field. This will cause the value to be stored in the view when the form is first loaded. The value can then be referenced many times without incurring database overhead.
If the method being called has not been declared static, use the new element to instantiate the class first, as shown in the following example.