Creating a class group

Create a class group using the Class Group form by selecting Class Group from the SysAdmin category. Creating appropriate class groups and the corresponding classes are important early steps in building an application. Typically, class groups are created by one of the following tools:

  • The New Application wizard creates a class group automatically.

  • The Import Archive tool also creates class groups when uploading a class rule that has is a class group in the This class field on the Settings tab.

  • The system creates a new class group automatically when you save a class rule that has is a class group in the This class field on the Settings tab.

A class group has one key part, which is the name of an abstract or concrete class. Objects of this class (and of subclasses of this class, except as overridden by other class group instances) are stored in a single database table.

To define a class group for a work pool, you can use the New Application wizard. If you use the New Application wizard to create an initial application, it creates a class group for the work pool automatically, incorporating good design practice.

If you do not use the wizard, designing a class group for a work pool and for the corresponding Work- classes involves several steps. Complete the following steps to create one class group and one work pool.

  1. Determine the parent class of all the classes that are to become associated with the class group.
  2. Designate one concrete class to be the "container". This class has the same name as the class group.
  3. Complete a class form for the container class. Make this a concrete class derived from Work-Object-, Work-Cover- or another appropriate class. Choose Is a class group in the This class field. On the Keys tab of the form, enter the property pyID as the only key part. When you save the class form, the system creates both the class you define, a history class, and a Class Group data instance. Choose the Short Description text carefully, it defines the application name.
  4. Complete the Class form again for each of the child classes derived from the container class. Select is a member of a class group for these classes. Do not complete the Keys array for these classes.
  5. Update the access groups of developers, testers, or users who need to use the application. Add the class group to the Work Pools list.
  6. Add properties and other rules as needed for the new classes.