Abstract The focus of the paper is to reveal the relationships between software maintainability and other internal software quality attributes. The source code characteristics of five Java‐based open‐source software products are analyzed using the software measurement tool SoftCalc. The relationships between maintainability and internal quality attributes are identified based on the Pearson product moment correlation analysis. Our results show negative correlations between maintainability and some well‐known internal software quality attributes, as well as the ones between maintainability and complexity metrics. Particularly, according to our results, the Number of Data Variables Declared and the Decisional Complexity McClure Metric have the strongest correlations with maintainability. The results of our study, that is to say, knowledge about the relationships between internal software quality attributes and maintainability, can be used as a basis for improvement of software maintainability at earlier stages of the software development process. Copyright © 2007 John Wiley & Sons, Ltd.

The paper focuses on measuring and assessing the relation of adaptive maintenance process and quality of open source software (OSS). A framework for assessing adaptive maintenance process is proposed and applied. The framework consists of six sub- processes. Five OSSs with considerable number of releases have been studied empirically. Their main evolutionary and quality characteristics have been measured. The main results of the study are the following:. 1) Software maintainability is affected mostly by the activities of the 'analysis' maintenance sub-process. 2) Software testability is affected by the activities of all maintenance sub-processes. 3) Software reliability is affected mostly by the activities of the 'design' and 'delivery' maintenance sub- processes. 4) Software complexity is affected mostly by the activities of the 'problem identification', design', 'implementation' and 'test' sub-processes. 5) Software flexibility is affected mostly by the activities of the 'delivery' sub-process.

The main problems in assessing the information quality of a particular kind of location-based service are described. Verifying the conformance of query results to the real world is identified as the most expensive problem. An approach from database quality assessment is adapted, by combining it with conventional software reliability testing, so that the verification can be replaced with two significantly easier test obligations. The resulting procedure should achieve a good compromise between the confidence level of the results and the testing effort. The approach seems also applicable to a broader range of systems.

The Unified Modeling Language (UML) provides various diagram types for describing a system from different perspectives or abstraction levels. Hence, UML diagrams describing the same system are dependent and strongly overlapping. In this paper we study how this can be exploited for specifying transformation operations between different diagram types. We discuss various general approaches and viewpoints of model transformations in UML. The source and target diagram types for useful transformations are analyzed and given categories. The potentially most interesting transformation operations are discussed in detail. It is concluded that the transformation operations can automate a substantial part of both forward and reverse engineering. These operations can be used, for example, for model checking, merging, slicing, and synthesis.