Baowen Xu

Test Case Prioritization for Black Box Testing

Test case prioritization is an effective and practical technique that helps to increase the rate of regression fault detection when software evolves. Numerous techniques have been reported in the literature on prioritizing test cases for regression testing. However, existing prioritization techniques implicitly assume that source or binary code is available when regression testing is performed, and therefore cannot be implemented when there is no program source or binary code to be analyzed. In this paper, we presented a new technique for black box regression testing, and we performed an experiment to measure our technique. Our results show that the new technique is helpful to improve the effectiveness of fault detection when performing regression test in black box environment.

Greedy Heuristic Algorithms to Generate Variable Strength Combinatorial Test Suite

Combinatorial testing is a practical software testing approach that has been widely used in practice. Most research and applications of such approach focus on N-way combinatorial testing that provides a minimum coverage of all N-way interactions among factor. However, the strengths of different interactions may not be a fixed integer N, but a variable. Therefore, variable strength combinatorial testing approach is necessary in applications. Existing variable strength combinatorial testing, which allows some interactions have a higher strength than others, has a limitation that such higher-strength interactions must be disjoint. To avoid such a limitation, an improved variable strength combinatorial testing approach, which makes a more sufficient consideration on actual interaction relationship, is proposed in this article. Furthermore, two greedy heuristic algorithms are also proposed to generate combinatorial test suite. Compared to some existing algorithms and tools, the proposed algorithms have advantages on both the execution effectiveness and the optimality of generated test suite. Experimental results can prove such advantages.

Regression testing for Web applications based on slicing

Web applications have rapid developing speed and changeable user demands, so the regression testing is much important. Since the changed demands result in different versions of Web applications, and the faults usually hiding in the adjusted contents, the regression testing must cover all the related pages. In order to carry through the regression testing quickly and effectively, we make the simplification with the method of slicing. Firstly, we analyze the possible changes in the Web applications and the influences produced by these changes, discussing in the direct-dependent and indirect-dependent way; next, we give the regression testing method based on slicing emphasized on the indirect-dependent among data, i.e., obtaining the dependent set of changed variables by forward and backward search method and generating the testing suits; conclusion remarks and future work are given at last.

Test Case Prioritization Based on Varying Testing Requirement Priorities and Test Case Costs

Test case prioritization is an effective and practical technique in regression testing. It schedules test cases in order of precedence that increases their ability to meet some performance goals, such as code coverage, rate of fault detection. In previous work, the test case prioritization techniques and metrics usually assumed that testing requirement priorities and test case costs are uniform. In this paper, basing on varying testing requirement priorities and test case costs, we present a new, general test case prioritization technique and an associated metric. The case study illustrates that the rate of units-oftesting-requirement-priority-satisfied- per-unit-test-case-cost can be increased, and then the testing quality and customer satisfaction can be improved.

A constrained non-negative matrix factorization in information retrieval

A novel method, which is called constrained non-negative matrix factorization, is presented to capture the latent semantic relations. An objective function is defined to impose three additional constraints, in addition to the non-negativity constraint in the standard non-negative matrix factorization. The update rules to solve the objective function with these constraints are presented, and its convergence is proved. In contrast to the standard non-negative matrix factorization, the constrained non-negative matrix factorization can capture the semantic relations as orthogonal as possible. The experiments indicate that the constrained non-negative matrix factorization has better precision than the standard non-negative matrix factorization in information retrieval.

A software debugging method based on pairwise testing

Pairwise testing is one of very practical and effective testing methods for various types of software systems. This paper proposes a novel debugging method based on pairwise testing. By analyzing the test cases and retesting with some complementary test cases, the method can narrow the factors that cause the errors in a very small range. So it can provide a very efficient and valuable guidance for the software testing and debugging.

A novel approach for test suite reduction based on requirement relation contraction

The goal of test suite reduction is to satisfy all testing requirements with the minimum number of test cases. Existing techniques can be applied well on the constructed test suite. However, it is possible and necessary to optimize testing requirements before test case generation. In this paper test suite reduction is solved by testing requirement optimization. A requirement relation graph is proposed to minimize the requirement set by graph contraction. An experiment on specification-based testing is designed and implemented. The empirical studies show that the testing requirements can be optimized by the graph contraction methods effectively.

Automatic test generation for n-way combinatorial testing

n-way combinatorial testing is a specification-based testing criterion, which requires that for a system consisting of a few parameters, every combination of valid values of arbitrary n (n ≥ 2) parameters be covered by at least one test. In this paper, we propose two different tests generation algorithms based on the combinatorial design for the n-way combination testing. We show that the produced tests can cover all the combinations of parameters to the greatest degree with the small quantity. We implemented the automatic test generators based on the algorithms and obtained some valuable empirical results.

A browser compatibility testing method based on combinatorial testing

For ensuring the displaying effects of Web applications, it is important to perform compatibility testing for browsers under the different configurations and it is a hard task to test all. So this paper focused on the improvements for browser compatibility testing. Firstly, we introduced the related work. Then we analysed the functional speciality of the current popular browsers, and provided the preconditions to simplify problems. Next we gave an instance and brought forward the single factor covering method and the pair-wise covering design to gain testing suits. Finally, we introduced the assistant tools we have developed and the future work.

Agentification for web services

We report our effort on the AgenEvo project, which develops an evolution approach to re-engineer legacy systems into agent-based Web services. We first survey the key technologies, which are adopted in this paper. After discussing the basic features of the Web services and agent, we focus on agent-based Web services, which are hot spot in web-based research area. We argue that agent-based Web services are well suited to building software solutions for distributed, open and dynamic web-based systems. Next, we introduce our approach on re-engineering framework and working flow. The method that integrates agents with Web services for legacy system evolution is proposed and an example on how to use agent-based Web services software evolution framework and methodology to re-engineer the legacy system is illustrated. Finally, we conclude the paper and suggest the directions of the possible future research.