International Journal of Software Engineering and Knowledge Engineering

Model-based testing has been intensively and extensively studied in the past decades. Extended Finite State Machine (EFSM) is a widely used model of software testing in both academy and industry. This paper provides a survey on EFSM-based test case generation techniques in the last two decades. All techniques in EFSM-based test case generation are mainly classified into three parts: test sequence generation, test data generation, and test oracle construction. The key challenges, such as coverage criterion and feasibility analysis in EFSM-based test case generation are discussed. Finally, we summarize the research work and present several possible research areas in the future.

Property specification is still one of the most challenging tasks for transference of software verification technology. The use of patterns has been proposed in order to hide the complicated handling of formal languages from the developer. However, this goal is not entirely satisfied. When validating the desired property the developer may have to deal with the pattern representation in some particular formalism. For this reason, we identify four desirable quality attributes for the underlying specification language: succinctness, comparability, complementariness, and modifiability. We show that typical formalisms such as temporal logics or automata fail at some extent to support these features. Given this context we introduce Featherweight Visual Scenarios (FVS), a declarative and graphical language based on scenarios, as a possible alternative to specify behavioral properties. We illustrate FVS applicability by modeling all the specification patterns and we thoroughly compare FVS to other known approaches, showing that FVS specifications are better suited for validation tasks. In addition, we augment pattern specification by introducing the concept of violating behavior. Finally we characterize the type of properties that can be written in FVS and we formally introduce its syntax and semantics.

Software architecture reconstruction plays an important role in software reuse, evolution and maintenance. Clustering is a promising technique for software architecture reconstruction. However, the representation of software, which serves as clustering input, and the clustering algorithm need to be improved in real applications. The representation should contain appropriate and adequate information of software. Furthermore, the clustering algorithm should be adapted to the particular demands of software architecture reconstruction well. In this paper, we first extract Weighted Directed Class Graph (WDCG) to represent object-oriented software. WDCG is a structural and quantitative representation of software, which contains not only the static information of software source code but also the dynamic information of software execution. Then we propose a WDCG-based Clustering Algorithm (WDCG-CA) to reconstruct high-level software architecture. WDCG-CA makes full use of the structural and quantitative information of WDCG, and avoids wrong compositions and arbitrary partitions successfully in the process of reconstructing software architecture. We introduce four metrics to evaluate the performance of WDCG-CA. The results of the comparative experiments show that WDCG-CA outperforms the comparative approaches in most cases in terms of the four metrics.

Usability is a software system quality attribute. Although software engineers originally considered usability to be related exclusively to the user interface, it was later found to affect the core functionality of software applications. As of then, proposals for addressing usability at different stages of the software development cycle were researched. The objective of this paper is to present three reusable solutions at detailed design and programming level in order to effectively implement the Abort Operation, Progress Feedback and Preferences usability functionalities in web applications. To do this, an inductive research method was applied. We developed three web applications including the above usability functionalities as case studies. We looked for commonalities across the implementations in order to induce a general solution. The elements common to all three developed applications include: application scenarios, functionalities, responsibilities, classes, methods, attributes and code snippets. The findings were specified as an implementation-oriented design pattern and as programming patterns in three languages. Additional case studies were conducted in order to validate the proposed solution. The independent developers used the patterns to implement different applications for each case study. As a result, we found that solutions specified as patterns can be reused to develop web applications.

The testing of RFID information services requires a test data set of business events comprising object, aggregation, quantity and transaction events. To generate business events, we need to address the performance issues in creating a large volume of event data. This paper proposes a new model for the tag life cycle and a fast generation algorithm for this model. We present the results of experiments with the generation algorithm, showing that it outperforms previous methods.

Software aging refers to the phenomenon that software systems show progressive performance degradation or a sudden crash after longtime execution. It has been reported that this phenomenon is closely related to the exhaustion of system resources. This paper quantitatively studies available system resources under the real-world situation where workload changes dynamically over time. We propose a neural network approach to first investigate the relationship between available system resources and system workload and then to forecast future available system resources. Experimental results on data sets collected from real-world computer systems demonstrate that the proposed approach is effective.