Three empirical studies of a software reuse reference model

The contribution of this paper is a reference model for the practice of software reuse. Our research thesis is that software development based upon a software reuse reference model improves quality of products, productivity of processes and product time‐to‐market for many software development enterprises. The definition and investigation of such a model has been carried out using three steps. First, the reference model is developed based on existing software reuse concepts. Second, this reference model is empirically studied using both legacy studies and lessons learned studies. Third, the impact of the reference model on software development productivity, quality, and time‐to‐market is empirically derived. Copyright © 2000 John Wiley & Sons, Ltd.     

Three empirical evaluations of a software reuse reference model

The contribution of this paper is three empirical evaluations of a reference model for the practice of software reuse. Our research thesis is that software development based upon a software reuse reference model improves quality of products, productivity of processes and product time‐to‐market for many software development enterprises. The definition and investigation of such a model has been carried out using three steps. First, the reference model is developed based on existing software reuse concepts. Second, this reference model is empirically evaluated using three studies: one using a survey method, one using a case studies method, and one using a legacy studies method. Third, the impact of the reference model on software development productivity, quality, and time‐to‐market is empirically derived. This revised version was published online in June 2006 with corrections to the Cover Date.     

Effects of reuse on quality, productivity, and economics

This article presents metrics from two Hewlett-Packard (HP) reuse programs that document the improved quality, increased productivity, shortened time-to-market, and enhanced economics resulting from reuse. Work products are the products or by-products of the software-development process: for example, code, design, and test plans. Reuse is the use of these work products without modification in the development of other software. Leveraged reuse is modifying existing work products to meet specific system requirements. A producer is a creator of reusable work products, and the consumer is someone who uses them to create other software. Time-to-market is the time it takes to deliver a product from the time it is conceived. Experience with reuse has been largely positive. Because work products are used multiple times, the accumulated defect fixes result in a higher quality work product. Because the work products have already been created, tested, and documented, productivity increases because consumers of reusable work products need to do less work. However, increased productivity from reuse does not necessarily shorten time-to-market. To reduce time-to-market, reuse must be used effectively on the critical path of a development project. Finally, we have found that reuse allows an organization to use personnel more effectively because it leverages expertise. However, software reuse is not free. It requires resources to create and maintain reusable work products, a reuse library, and reuse tools. To help evaluate the costs and benefits of reuse, we have developed an economic analysis method, which we have applied to multiple reuse programs at HP     

Toward a reference process for developing wireless Internet services

Wireless Internet services such as mobile Web applications promise an enormous market potential. The field is characterized by extreme time-to-market pressure and insufficient knowledge about development procedures and technical constraints. This results in insufficient guidance for project managers and software developers on selecting appropriate development processes, techniques, methods, and tools. In addition, there is an enormous lack of knowledge about the effects (such as effort consumption, defect injection) of such technologies that hinders the transfer of innovative technologies into practice. This article describes an initial reference process by summarizing essential technologies for the development of wireless Internet services and experience with these technologies on the levels of life cycle processes, engineering processes, and managerial processes. The reference process is based on a comprehensive literature survey and the execution of development projects for wireless Internet services. The goal of the article is to provide domain-specific guidance for project managers and software developers with accompanying lessons learned from the past.     

Facilitating experience reuse among software project managers

Organizations have lost billions of dollars due to poor software project implementations. In an effort to enable software project managers to repeat prior successes and avoid previous mistakes, this research seeks to improve the reuse of a specific type of knowledge among software project managers, experiences in the form of narratives. To meet this goal, we identify a set of design principles for facilitating experience reuse based on the knowledge management literature. Guided by these principles we develop a model called Experience Exchange for facilitating the reuse of experiences in the form of narratives. We also provide a proof-of-concept instantiation of a critical component of the Experience Exchange model, the Experience Exchange Library. We evaluate the Experience Exchange model theoretically and empirically. We conduct a theoretical evaluation by ensuring that our model complies with the design principles identified from the literature. We also perform an experiment, using the developed instantiation of the Experience Exchange Library, to evaluate if technology can serve as a medium for transferring experiences across software projects.     

Toward an engineering discipline of software reuse

This article stems from a panel session at the 1997 Symposium on Software Reusability, and discusses open research issues, classified by goal and by approach. Software development cannot possibly become an engineering discipline so long as it has not perfected a technology for developing products from reusable assets in a routine manner, on an industrial scale. Software reuse cannot, in turn, achieve this status unless we make the following provisions: a sound scientific foundation that encompasses relevant design principles, widely acceptable engineering standards that compile these principles into working practical solutions, and coherent managerial standards that enable the deployment of these solutions under acceptable conditions of product quality and process maturity. Although successful software reuse experiments are increasingly common, success is not the norm, software reuse is not a matter of routine practice, the promises of software reuse remain for the most part unfulfilled, and a number of issues remain worthy of further research     

A software reuse measure: Monitoring an enterprise-level model driven development process

The purpose of the research discussed here is to establish a metric for the measurement of reuse in a generic enterprise-level model context and to use this approach to create a specific metric for a company. The paper demonstrates how a software development firm can monitor the reuse success in the development process using the measure. Traditionally, the reuse rate is defined as the percentage of the development effort retrieved as code segments from a software repository. The metric proposed here extends this definition to include reuse of generic enterprise-level model components. An example is given of the successful assessment of a reuse percentage for a software developer's actual project.     

Large-scale industrial reuse to reduce cost and cycle time

For long-term software reuse strategies to work, companies must realize short-term successes. The authors' company improved its time-to-market, productivity and quality by pursuing reuse in two large industrial projects     

Assessment and cross-product prediction of software product line quality: accounting for reuse across products,over multiple releases

The goals of cross-product reuse in a software product line (SPL) are to mitigate production costs and improve the quality. In addition to reuse across products, due to the evolutionary development process, a SPL also exhibits reuse across releases. In this paper, we empirically explore how the two types of reuse—reuse across products and reuse across releases—affect the quality of a SPL and our ability to accurately predict fault proneness. We measure the quality in terms of post-release faults and consider different levels of reuse across products (i.e., common, high-reuse variation, low-reuse variation, and single-use packages), over multiple releases. Assessment results showed that quality improved for common, low-reuse variation, and single-use packages as they evolved across releases. Surprisingly, within each release, among preexisting (‘old’) packages, the cross-product reuse did not affect the change and fault proneness. Cross-product predictions based on pre-release data accurately ranked the packages according to their post-release faults and predicted the 20 % most faulty packages. The predictions benefited from data available for other products in the product line, with models producing better results (1) when making predictions on smaller products (consisting mostly of common packages) rather than on larger products and (2) when trained on larger products rather than on smaller products.     

非基于软件复用的成本估算模型的复用改造模型及模型系数修正策略

作为软件成本控制管理的重要措施,软件开发成本的估算技术已经成为软件工程领域的一个重要课题。当前基于复用的软件开发正在成为软件工程的主流,但将软件复用考虑进成本估算的模型较少。提出一个基于软件复用的成本估算模型,并应用该模型对COCOMO模型进行复用改造,之后通过实例进行验证。给出了使用存储过程技术对模型参数进行修正的策略,以为各类基于复用的软件开发成本估算提供依据。     

Towards a formal framework for software reuse

It is reasonable to expect that the use of formal methods in software reuse will help improve the practice of this discipline as well as enhance our understanding of its products and processes. We have identified the following technical activities that take place in software reuse as candidates for a formal modeling: representing reusable assets, representing reuse queries, defining matching criteria, defining a storage structure, deriving measures of distance and deriving a calculus of program modification. In this paper we discuss how a simple mathematical model based on set theory and relation theory allows us to capture these activities in a unified, coherent framework.     

Representing variability in a family of MRI scanners

Promoting software reuse is probably the most promising approach to the cost‐effective development and evolution of quality software. An example of reuse is the successful adoption of software product families in industry. In a product family context, software architects anticipate product variation and design architectures that support product derivation in both space (multiple contexts) and time (changing contexts). Product derivation is based on the concept of variability: a single architecture and a set of components support a family of products. Modern software product families need to support increasing amounts of variability, leading to a situation where variability engineering becomes of primary concern. Variability is often introduced as an ‘add‐on’ to the system without taking the consequences for more than one lifecycle phase such as design or architecture into account. This paper (1) suggests a Variability Categorization and Classification Model (VCCM) for representing variability in the software lifecycle and (2) discusses a case study of a large‐scale software product family of Magnetic Resonance Imaging (MRI) scanners developed by Philips Medical Systems. The study illustrates how variability can be made an integral part of system development at different levels of abstraction. VCCM has been applied to the scanner family as an analysis tool. Copyright © 2003 John Wiley & Sons, Ltd.     

Risk orientation in software testing processes of small and medium enterprises: an exploratory and comparative study

Risk orientation in testing is an important means to balance quality, time-to-market, and cost of software. Especially for small and medium enterprises (SME) under high competitive and economic pressure, risk orientation can help to focus testing activities on critical areas of a software product. Although several risk-based approaches to testing are available, the topic has so far not been investigated in the context of SME, where risks are often associated with business critical issues. This article fills the gap and explores the state of risk orientation in the testing processes of SME. Furthermore, it compares the state of risk-based testing in SME to the situation in large enterprises. The article is based on a multiple case study conducted with five SME. A previous study on risk-based testing in large enterprises is used as reference for investigating the differences between risk orientation in SME and large enterprises. The findings of our study show that a strong business focus, the use of informal risk concepts, as well as the application of risk knowledge to reduce testing cost and time are key differences of risk-based testing in SME compared to large enterprises.     

Towards a General Component Model for Web-Based Applications

The cost effective development of web applications is perhaps one of the most challenging areas of software engineering today. Not only are the problems to be solved, and the solution technologies to be used, in web application development among the most rapidly changing in the software industry, but the business pressures of cost, quality and time-to-market are among the most extreme. Web application development therefore has potentially the most to gain from software reuse approaches that can offer a greater return on development time than traditional approaches. However, simply combining ideas from these reuse paradigms and traditional web development technologies in ad-hoc ways will not result in sustainable improvements. In this paper we describe a systematic way of combining the benefits of component-based development and model driven architectures, two important reuse approaches, to support the cost effective development and maintenance of web applications. After first defining a suitably abstract component-model, the paper explains how component architectures can be systematically and rigorously modeled using UML. It then describes a powerful technique, known as stratification, for separating the various cross cutting aspects of a web application such that a suitable platform specific architecture can be traceably generated. Finally, the paper introduces a technique for increasing the trustworthiness of components by giving them the capability to check their deployment environment at run-time.     

基于构件化的软件产品开发研究

为了满足软件产品的开发对生产质量和开发周期提出的更高要求,阐述了标准化工作中的模块化在软件产品构件化开发中的重要性,回顾了基于构件的软件开发方式的发展历程,提出了基于构件的软件开发方式和相关的实施案例。通过构件化的开发方法,为企业提高了软件产品质量,缩短了产品上市的周期,取得了良好的经济效益。     

Reusing enterprise models to build platform independent computer models

Enterprises use enterprise models to represent and analyse their processes, products, decisions, organisation, information flows, etc. Nevertheless, the enterprise knowledge that exists in enterprise models is not used beyond these purposes. The main goal of this paper is to present a framework that allows enterprises to reuse enterprise models to build software. The framework includes these dimensions: (1) a methodology that guides the use of the other dimensions in the reutilisation of enterprise models in software generation; (2) a set of metamodels to represent enterprises at the Computation Independent Model (CIM) level; (3) a modelling guide to make enterprise models using the metamodels proposed in this paper; (4) an extraction algorithm to discriminate the part of the CIM model to reuse; and (5) a set of transformation rules to reuse enterprise models to build Platform Independent Models. In addition, a case example is shown to validate the work that was carried out and to identify limitations.     

Empirical assessment of the impact of structural properties on the changeability of object-oriented software

The changeability of software can be viewed as the quality of being capable of change, which among others implies that the task of changing the software requires little effort. It is hypothesized that structural properties of the software affect changeability, in which case measures of such properties can be used as changeability indicators.Ways in which structural properties of the software can be measured are described and empirically validated based on data collected from an industrial Java development project. The measures are validated by using them as candidate variables in a multivariate regression model of the actual effort required to make modifications to the evolving software system.The results suggest that some measures that combine existing structural attribute measures with a weighting factor based on the relative proportion of change in each class can explain a large amount of the variation in change effort. This constitutes initial, empirical evidence that the proposed measures are valid changeability indicators. Consequently, they may help designers to identify and correct design problems during the development and maintenance of object-oriented software.     

Improved estimation of software project effort using multiple additive regression trees

Accurate estimation of software project effort is crucial for successful management and control of a software project. Recently, multiple additive regression trees (MART) has been proposed as a novel advance in data mining that extends and improves the classification and regression trees (CART) model using stochastic gradient boosting. This paper empirically evaluates the potential of MART as a novel software effort estimation model when compared with recently published models, in terms of accuracy. The comparison is based on a well-known and respected NASA software project dataset. The results indicate that improved estimation accuracy of software project effort has been achieved using MART when compared with linear regression, radial basis function neural networks, and support vector regression models.     

Key activities for product derivation in software product lines

More and more organizations adopt software product lines to leverage extensive reuse and deliver a multitude of benefits such as increased quality and productivity and a decrease in cost and time-to-market of their software development. When compared to the vast amount of research on developing product lines, relatively little work has been dedicated to the actual use of product lines to derive individual products, i.e., the process of product derivation. Existing approaches to product derivation have been developed independently for different aims and purposes. While the definition of a general approach applicable to every domain may not be possible, it would be interesting for researchers and practitioners to know which activities are common in existing approaches, i.e., what are the key activities in product derivation. In this paper we report on how we compared two product derivation approaches developed by the authors in two different, independent research projects. Both approaches independently sought to identify product derivation activities, one through a process reference model and the other through a tool-supported derivation approach. Both approaches have been developed and validated in research industry collaborations with different companies. Through the comparison of the approaches we identify key product derivation activities. We illustrate the activities’ importance with examples from industry collaborations. To further validate the activities, we analyze three existing product derivation approaches for their support for these activities. The validation provides evidence that the identified activities are relevant to product derivation and we thus conclude that they should be considered (e.g., as a checklist) when developing or evaluating a product derivation approach.     

Assessing the cost-effectiveness of software reuse: A model for planned reuse

Information systems development is typically acknowledged as an expensive and lengthy process, often producing code that is of uneven quality and difficult to maintain. Software reuse has been advocated as a means of revolutionizing this process. The claimed benefits from software reuse are reduction in development cost and time, improvement in software quality, increase in programmer productivity, and improvement in maintainability. Software reuse entails undeniable costs of creating, populating, and maintaining a library of reusable components. There is anecdotal evidence to suggest that some organizations benefit from reuse. However, many software developers practicing reuse claim these benefits without formal demonstration thereof. There is little research to suggest when the benefits are expected and to what extent they will be realized. For example, does a larger library of reusable components lead to increased savings? What is the impact of component size on the effectiveness of reuse? This research seeks to address some of these questions. It represents the first step in a series wherein the effects of software reuse on overall development effort and costs are modeled with a view to understanding when it is most effective.