Class

Informally, a class is a name that serves as a grouping or container for a collection of rules or other objects. For example, if a class is named MyCo_Mortgage, rules that are associated with that class have that name as a first key part, known as the Applies To key part. A work object that "belongs" to that class has MyCo_Mortgage as a portion of its unique key, though only the work object ID portion (not the class) appears in most displays.

Formally, a class an instance of the Rule-Obj-Class rule type. Each class defines capabilities (rules such as properties, activities, HTML forms, and so on) available to other, subordinate classes, or to instances of the class.

Classes are organized into a hierarchy. The ultimate base class — named @baseclass — is at the top (or left). The base classes — Data-, Rule-, Work- and others — are immediate child classes of the ultimate base class. Other classes are derived from the base classes.

The words up and top for the class hierarchy refer to the ultimate base class. The words down and bottom of the class hierarchy refer to the concrete classes, or classes that are parent to no other class. The parent of a class is above its child classes.

When looking for a rule to apply, the system searches the class hierarchy from the current class upwards. A property or activity or flow or HTML object named DressSize, defined in a concrete class at the fifth level of a hierarchy below the Work- class, supersedes a similar property named DressSize at the fourth, third, second, and first levels.

Concrete classes corresponding to instances saved in the PegaRULES database are known as internal classes. In a saved (persistent) instance of an internal class, on the clipboard page that has an associated class, the value of the pyObjClass property records the class of the current object.

Concrete classes corresponding to a table in an external relational database (rather than the PegaRULES database) are known as external classes.

A few help topics contain references to Java classes, not Rule-Obj-Class instances. In these topics the word Java always precedes the word class. In most help topics, class identifies a PRPC class, a Rule-Obj-Class instance.

Concrete classes derived from the Rule- base class are known as rule types. Concrete classes derived from the Work- base class are known as work types.

	abstract class, applicable rules, base class, concrete class, directed inheritance, external class, inheritance, internal class, pattern inheritance, rule type, top-level class, work type
	About Class rules Class hierarchy and inheritance — Concepts and terms

Definitions