物件導向軟體之架構(Object-Oriented Software Construction)探討

The use of metaheuristic search techniques for the automatic generation of test data has been a burgeoning interest for many researchers in recent years. Previous attempts to automate the test generation process have been limited, having been constrained by the size and complexity of software, and the basic fact that in general, test data generation is an undecidable problem. Metaheuristic search techniques oer much promise in regard to these problems. Metaheuristic search techniques are highlevel frameworks, which utilise heuristics to seek solutions for combinatorial problems at a reasonable computational cost. To date, metaheuristic search techniques have been applied to automate test data generation for structural and functional testing; the testing of grey-box properties, for example safety constraints; and also non-functional properties, such as worst-case execution time. This paper surveys some of the work undertaken in this eld, discussing possible new future directions of research for each of its dieren t individual areas.

https://www.inf.utfsm.cl/~mcriff/Tesistas/Testing/sbs-survey.pdf

Search‐based software test data generation: a survey

Metaheuristic techniques such as genetic algorithms, simulated annealing and tabu search have found wide application in most areas of engineering. These techniques have also been applied in business, financial and economic modelling. Metaheuristics have been applied to three areas of software engineering: test data generation, module clustering and cost/effort prediction, yet there remain many software engineering problems which have yet to be tackled using metaheuristics. It is surprising that metaheuristics have not been more widely applied to software engineering; many problems in software engineering are characterised by precisely the features which make metaheuristics search applicable. In the paper it is argued that the features which make metaheuristics applicable for engineering and business applications outside software engineering also suggest that there is great potential for the exploitation of metaheuristics within software engineering. The paper briefly reviews the principal metaheuristic search techniques and surveys existing work on the application of metaheuristics to the three software engineering areas of test data generation, module clustering and cost/effort prediction. It also shows how metaheuristic search techniques can be applied to three additional areas of software engineering: maintenance/evolution system integration and requirements scheduling. The software engineering problem areas considered thus span the range of the software development process, from initial planning, cost estimation and requirements analysis through to integration, maintenance and evolution of legacy systems. The aim is to justify the claim that many problems in software engineering can be reformulated as search problems, to which metaheuristic techniques can be applied. The goal of the paper is to stimulate greater interest in metaheuristic search as a tool of optimisation of software engineering problems and to encourage the investigation and exploitation of these technologies in finding near optimal solutions to the complex constraint-based scenarios which arise so frequently in software engineering.

/pdf/reformulating-software-engineering-as-a-search-problem-36493jndeg.pdf

Reformulating software engineering as a search problem

Recent studies in the literature have shown that syntax remains a significant barrier to novice computer science students in the field. While this syntax barrier is known to exist, whether and how it varies across programming languages has not been carefully investigated. For this article, we conducted four empirical studies on programming language syntax as part of a larger analysis into the, so called, programming language wars. We first present two surveys conducted with students on the intuitiveness of syntax, which we used to garner formative clues on what words and symbols might be easy for novices to understand. We followed up with two studies on the accuracy rates of novices using a total of six programming languages: Ruby, Java, Perl, Python, Randomo, and Quorum. Randomo was designed by randomly choosing some keywords from the ASCII table (a metaphorical placebo). To our surprise, we found that languages using a more traditional C-style syntax (both Perl and Java) did not afford accuracy rates significantly higher than a language with randomly generated keywords, but that languages which deviate (Quorum, Python, and Ruby) did. These results, including the specifics of syntax that are particularly problematic for novices, may help teachers of introductory programming courses in choosing appropriate first languages and in helping students to overcome the challenges they face with syntax.

An Empirical Investigation into Programming Language Syntax

A testability transformation is a source-to-source transformation that aims to improve the ability of a given test generation method to generate test data for the original program. We introduce testability transformation, demonstrating that it differs from traditional transformation, both theoretically and practically, while still allowing many traditional transformation rules to be applied. We illustrate the theory of testability transformation with an example application to evolutionary testing. An algorithm for flag removal is defined and results are presented from an empirical study which show how the algorithm improves both the performance of evolutionary test data generation and the adequacy level of the test data so-generated.

/pdf/testability-transformation-2po6cl49xh.pdf

Testability transformation

This paper reports the results of a study on the impact of a type of side effect (SE) upon program comprehension. We applied a crossover design on different tests involving fragments of C code that include increment and decrement operators. Each test had an SE version and a side-effect-free counterpart. The variables measured in the treatments were the number of correct answers and the time spent in answering. The results show that the side-effect operators considered significantly reduce performance in comprehension-related tasks, providing empirical justification for the belief that side effects are harmful.

/pdf/an-empirical-investigation-of-the-influence-of-a-type-of-fvr1fvdq2c.pdf

An empirical investigation of the influence of a type of side effects on program comprehension

There is a certain degree of difficulty in developing and understanding the diagrams used for representing the dynamic behavior of a software application, specified in the Unified Modeling Language (UML). In this paper we evaluate the comprehension of the dynamic modeling in UML designs by using two split-plot factorial experiments. The metrics used for assessing the results are the time spent and the scores obtained in answering a questionnaire. In the first study three factors were controlled: the diagram type (sequence, collaboration and state), the application domain of the UML designs and the order of presentation of the documents. We observe that state diagrams provide higher semantic comprehension of dynamic modeling in UML when the domain is real-time and sequence diagrams are better in the case of a management information application. In the second study two factors were controlled: the paired combination of dynamic diagrams and the application domain. The main conclusion of the second study is that regardless of the domain, a higher semantic comprehension of the UML designs is achieved when the dynamic behavior is modeled by using the pair Sequence–State. Combining the results of both experiments we obtain the conditions which must concur to get an effective comprehension of the UML dynamic models: (a) if it is a management information application, the diagrams are sequence or the composition Sequence–State or Collaboration–State; (b) for a real-time non-reactive system the diagrams are collaboration or the pair Collaboration–State or Sequence–State; and (c) finally, when it is the design of the real-time reactive system, the best diagram is the State.

Evaluation of the comprehension of the dynamic modeling in UML

Side-effects are widely believed to impede program comprehension and have a detrimental effect upon software maintenance. This paper introduces an algorithm for side-effect removal which splits the side-effects into their pure expression meaning and their state-changing meaning. Symbolic execution is used to determine the expression meaning, while transformation is used to place the state-changing part in a suitable location in a transformed version of the program. This creates a program which is semantically equivalent to the original but guaranteed to be free from side-effects. The paper also reports the results of an empirical study which demonstrates that the application of the algorithm causes a significant improvement in program comprehension.

/pdf/a-post-placement-side-effect-removal-algorithm-2imljz7gue.pdf

A post-placement side-effect removal algorithm

In this paper a modular generic architecture for cyber-physical systems based on free open software components is presented. The architecture is implemented over inexpensive components frequently found in information and communication technology contexts. More specifically, the robot operating system middleware abstracts communication among multiple networked modules, whereas the Docker lightweight virtualization container is proposed to wrap up software modules. Focus is on mobile robotics in production systems and industrial automation environments. Actually, an automated guided vehicle problem is demonstrated by means of a proof of concept aimed at industrial automation applications illustrating the potential of the proposed architecture and its implementation, built with low cost hardware modules.

A modular CPS architecture design based on ROS and Docker

The goal of this empirical study is to compare the semantic comprehension of three different notations for representing the dynamic behaviour in unified modelling language (UML): (a) sequence diagrams, (b) collaboration diagrams, and (c) state diagrams. Eighteen students of Informatics analysed the three types of diagrams within three different application domains. We performed a 3 × 3 factorial experimental design with repeated measures. The metrics collected were total time and total score. The main conclusion of this study is that the comprehension of the dynamic modelling in object-oriented designs depends on the diagram type and on the complexity of the document. The software project design written in the UML notation is more comprehensible, when the dynamic behaviour is modelled in a sequence diagram. While if it is implemented using a collaboration diagram, the design turns out to be less comprehensible as the application domain, and consequently, the document is more complex.

Mari Carmen Otero

Papers

An empirical investigation of the influence of a type of side effects on program comprehension

Evaluation of the comprehension of the dynamic modeling in UML

A post-placement side-effect removal algorithm

A modular CPS architecture design based on ROS and Docker

An Initial Experimental Assessment of the Dynamic Modelling in UML