Design Recovery for Software Testing ofObject - Oriented

Object-oriented features such as encapsulation, inheritance, and state dependent behavior raise new problems in software testing. In this paper, we describe a reverse engineering approach for software testing of object-oriented programs. The approach is based on a graphic model which consists of three types of diagrams: object relation diagram, block branch diagram, and object state diagram. An object relation diagram presents the inheritance, aggregation, and association relations among the object classes. A block branch diagram presents, for a member function, the control structure, the input parameters and output parameters, the external data that are used and aaected, and other functions that are invoked. An object state diagram presents the states and state transitions. Rules for generating these diagrams from a C++ program will be described. These diagrams may be used to 1) provide guidance on the order to test the classes and member functions; 2) prepare member function test cases; 3) prepare test cases for object state dependent hehaviors and interaction between such behaviors; and 4) provide graphic display of coverage information to a tester.