Book Image

Sonar Code Quality Testing Essentials

By : Charalampos S Arapidis
Book Image

Sonar Code Quality Testing Essentials

By: Charalampos S Arapidis

Overview of this book

Sonar is an open source platform used by development teams to manage source code quality. Sonar has been developed with this main objective in mind: make code quality management accessible to everyone with minimal effort. As such, Sonar provides code analyzers, reporting tools, manual reviews, defect-hunting modules, and TimeMachine as core functionalities. It also comes with a plugin mechanism enabling the community to extend the functionality, making Sonar the one-stop-shop for source code quality by addressing not only the developer's requirements, but also the manager's needs.The "Sonar Code Quality Testing Essentials" book will help you understand the different factors that define code quality and how to improve your own or your team's code using Sonar. You will learn to use Sonar effectively and explore the quality of your source code in the following axes: Coding Standards Documentation and Comments Potential Bugs and Defects Unit Testing Coverage Design and Complexity Through practical examples, you will customize Sonar components and widgets to identify areas where your source code is lacking. The book goes down to proposing good practices and common solutions that you can put to use to improve such code.You will start with installing and setting up a Sonar server and performing your first project analysis. Then you will go through the process of creating a custom and balanced quality profile exploring all Sonar components through practical examples. After reading the book, you will be able to analyze any project using Sonar and know how to read and evaluate quality metrics.Hunting potential bugs and eliminating complexity are the hottest topics regarding code quality. The book will guide you through the process of finding such problematic areas, leveraging and customizing the most appropriate components. Knowing the best tool for each task is essential. While you improve code and design through the book, you will notice that metrics go high and alerts turn green. You will use the Time Machine and the Timeline to examine how your changes affected the quality."Sonar Code Quality Testing Essentials" will enable you to perform custom quality analysis on any Java project and quickly gain insight on even large code bases, as well as provide possible solutions to code defects and complexity matters.
Table of Contents (18 chapters)
Sonar Code Quality Testing Essentials
Credits
About the Author
About the Reviewers
www.PacktPub.com
Preface
Sonar Metrics Index

Lack of Cohesion in Methods and the LCOM4 metric


The Lack of Cohesion in Methods (LCOM) metric measures the cohesion of a class and it was first introduced in the Chidamber & Kemerer metrics suite in 1993. Since then, the metric was redefined and revised numerous times, with LCOM5 being the latest version.

Sonar incorporates version four of the metric, hence the LCOM4 naming. The metric measures the degree to which methods and fields within a class are related to one another, providing one or more components. To calculate the LCOM4 value, we have to determine how many connected groups of related methods and fields exist in a class:

  • LCOM4 = 1: The class is a solid component with all methods and fields related

  • LCOM4 > 1: The class can be split to different classes

  • LCOM4 = 0: The class has no methods

According to the single responsibility principle, a class should provide a single component with all methods and fields related. This is the case when LCOM4 = 1. Otherwise, the class lacks...