Pak-Lok Poon

An integrated classification-tree methodology for test case generation

This paper describes an integrated methodology for the construction of test cases from functional specifications using the classification-tree method. It is an integration of our extensions to the classification-hierarchy table, the classification tree construction algorithm, and the classification tree restructuring technique. Based on the methodology, a prototype system ADDICT, which stands for AutomateD test Data generation system using the Integrated Classification-Tree method, has been built.

On the identification of categories and choices for specification-based test case generation

The category-partition method and the classification-tree method help construct test cases from specifications. In both methods, an early step is to identify a set of categories (or classifications) and choices (or classes). This is often performed in an ad hoc manner due to the absence of systematic techniques. In this paper, we report and discuss three empirical studies to investigate the common mistakes made by software testers in such an ad hoc approach. The empirical studies serve three purposes: (a) to make the knowledge of common mistakes known to other testers so that they can avoid repeating the same mistakes, (b) to facilitate researchers and practitioners develop systematic identification techniques, and (c) to provide a means of measuring the effectiveness of newly developed identification techniques. Based on the results of our studies, we also formulate a checklist to help testers detect such mistakes.

Investigating ERP systems procurement practice: Hong Kong and Australian experiences

Context: Integration of information systems is now commonly recognized to be a powerful strategic weapon that sharpens the competitive edge of a firm in todays highly volatile business environment. Such integration can be achieved by replacing the disconnected and incompatible legacy applications by enterprise resource planning (ERP) systems. Along with the remarkable growth of the ERP market, we have seen a number of failure cases of ERP adoption. Such failure cases indicate that not all firms know how to adopt an ERP solution effectively. Objective: To explore and identify crucial practices from real experiences in the Asia-Pacific region that may explain a firms success in ERP procurement, with an overt intention toward the formulation of useful lessons that inform practitioners and contribution to advances in software development practices in organizations. Method: A multiple-case design involving three Chinese firms based in Hong Kong and a local firm in Australia was employed. We collected, verified, and analyzed the information about the ERP procurement practice in each subject firm by means of semi-structured interviews, archive reviews, and member checks. Results: We summarized our results in the form of 10 lessons learned, together with observations of how culture seems to have played a part in shaping the practice. Conclusion: Our results offer practical guidelines originated from real cases that are of use for practitioners to improve the ERP procurement process.

Construction of classification trees via the classification-hierarchy table

Abstract The classification-tree method developed by Grochtmann and coworkers is a black box testing technique to assist test engineers to construct test cases systematically from the functional specifications, via the construction of classification trees. This paper supplements their studies by proposing a methodology to construct classification trees systematically from given sets of classifications and their associated classes, via the notion of the classification-hierarchy table. The intuition of the classification-hierarchy table is to capture the hierarchical relationship for every pair of distinct classifications from which classification trees can be constructed.

Experience with teaching black-box testing in a computer science/software engineering curriculum

Software testing is a popular and important technique for improving software quality. There is a strong need for universities to teach testing rigorously to students studying computer science or software engineering. This paper reports the experience of teaching the classification-tree method as a black-box testing technique at the University of Melbourne, Melbourne, Australia, and Swinburne University of Technology, Melbourne, Australia. It aims to foster discussion of appropriate teaching methods of software testing.

Contributions of tester experience and a checklist guideline to the identification of categories and choices for software testing

An early step for most black-box testing methods is to identify a set of categories and choices (or their equivalents) from the specification. The identification is often performed in an ad hoc manner, thus the quality of categories and choices is in doubt. Poorly identified categories and choices will affect the comprehensiveness of test cases. In this paper, we describe several comparative studies using three commercial specifications and discuss the major results. The objectives of our studies are (a) to investigate the differences in the types and amounts of mistakes made between inexperienced and experienced software testers in an ad hoc identification approach and (b) to determine the extent of mistake reduction after discussing the mistakes with the software testers and providing them with an identification checklist.

Procurement of enterprise resource planning systems: experiences with some Hong Kong companies

Many cases of adoption of Enterprise Resource Planning (ERP) systems have been reported in the literature. Some of the adopted ERP systems fail to satisfy the customers requirements, despite the high spending and substantial efforts that have been put into the adoption exercise. This is undoubtedly unsatisfactory. A way to avoid this problem is to adopt a well planned, managed, and controlled ERP procurement process. This paper describes our studies of three Chinese companies in Hong Kong which have adopted ERP systems. We report the experience of these companies, and discuss how the Chinese culture might have shaped the procurement practices in their ERP adoption exercises.

Classification-Hierarchy Table: a methodology for constructing the classification tree

The Classification-Tree Method developed by Grochtmann and Grimm (1993) provides a systematic approach to produce test cases based on the functional specification. This paper supplements the Classification-Tree Method by proposing a methodology to construct a classification-tree from a given set of classifications and classes based on the notion of Classification-Hierarchy Table. The Classification-Hierarchy Table is used to capture the hierarchy of a classification tree. From this table, useful information such as the relative level of the classifications in the tree, their parent classifications and parent classes could be obtained to guide the construction of the classification tree.

Towards a problem-driven approach to perspective-based reading

The quality of a requirements specification has a great impact on the quality of the software developed. Because of this, a requirements specification should be complete, correct, consistent, and unambiguous. Otherwise, defects may remain undetected, resulting in the delivery of a faulty software product to the users. Motivated by this, Basili et al. have developed the perspective-based reading (PBR) technique to help identify defects in requirements specifications. In this paper we propose a problem-driven approach for supporting the PBR technique. We also discuss the experience of applying our proposal to a real-life requirements specification.

CHOC'LATE: a framework for specification-based testing

In spite of its importance in software reliability, testing is labor intensive and expensive. It has been found that software testing without a good strategy may not be more effective than testing the system with random data. Obviously, the effectiveness of testing relies heavily on how well the test suite --- the set of test cases actually used --- is generated. This is because the comprehensiveness of the test suite will affect the scope of testing and, hence, the chance of revealing software faults. There are two main approaches to generating test suites: specification-based and code-based. The former generates a test suite from information derived from the specification, without requiring the knowledge of the internal structure of the program. The latter approach, on the other hand, generates a test suite based on the source code of the program. Neither of these approaches is sufficient; they are complementary to one another. In software development, the requirements have to be established before implementation, and the specification should exist prior to coding. In this respect, the specification-based approach to test suite generation is particularly useful because test cases can be generated before coding has been completed. This facilitates software development phases to be performed in parallel, thus allowing time for preparing more thorough test plans and yet shortening the length of the whole process.