MF 

Class Definition

General Format


*

Syntax Rules

  1. The words PROTECTED and RESTRICTED are equivalent.
  2. If the EXTERNAL clause is specified, neither the DATA nor the INHERITS clause may be specified.
  3. If the ABSTRACT clause is specified, the FINAL clause must not be specified.
  4. If the WITH DATA phrase is specified in the INHERITS clause, the DATA IS PRIVATE clause must not be specified explicitly or implicitly in the source code for class-name-2.
  5. Class-name-2 must not be the same as class-name-1.
  6. Class-name-2 must not inherit from class-name-1 directly or indirectly.
  7. Class-name-1 in the END CLASS header must be identical to the class-name-1 specified in the preceding Class-ID paragraph.

General Rules

  1. Class-name-1 identifies the class being declared.
  2. The ABSTRACT clause indicates that class-name-1 is an abstract class. You cannot create an instance of an abstract class.
  3. The EXTERNAL phrase indicates that class-name-1 is an external class. No code is produced.
  4. The RESTRICTED phrase enables subclasses to directly access data inherited from class-name-1.
  5. The PRIVATE phrase prevents subclasses from directly accessing data inherited from class-name-1.
  6. The INHERITS phrase specifies that class-name-2 is a parent class of class-name-1.
  7. If the INHERITS phrase is not specified, class-name-1 forms a new root in the classification scheme. There can be one or more roots in a classification scheme.
  8. The WITH DATA phrase specifies that class-name-1 is able to access directly data inherited from class-name-2.