SmellyCat

SmellyCat is a simple tool that detects smells in your classes. The tool is based on Maurício Aniche's PhD thesis.

Currently, we only support two architectures: Spring MVC and Android. In Spring MVC, we evaluate the quality of your Controllers, Services, Components,Repositories, and Entities. In Android, we evaluate the quality of your Activity, Task, and Fragment.

Examples of the analysis: CK in SSP (Spring MVC), CK in AnyMemo (Android).

How to interpret?

SmellyCat produces a treemap. It means that the higher the class' square, the higher the metric value. However, it classifies the value in 4 categories. Green means that your class is below any risk limit. It means that, to the point of view of that metric, you should not be worried. Yellow means moderate risk. It means that you should start taking care of it. Light red means high risk, and dark red means very high risk. These are the classes you should be worried about, as they are very far from what we consider "good".

You can see the specific thresholds values in our paper.

CK metrics

SmellyCat analyses CK metrics in your architectural roles and uses Alves' et al approach to find moderate, high, and very high risk classes.

We use the following metrics:

• Weighted Methods Per Class (WMC). In a simple way, it is the sum of each method's complexity in a class. It is usually represented by the Number of McCabe, which is the number of different possible paths of execution in a method.

• Number of Methods (NOM). The number of methods in a class is also another common metric to explain the complexity of a class. Some tools even use NOM instead of McCabe's Number to represent WMC.

• Coupling Between Object Classes (CBO). The number of classes a class depends upon. It counts classes used from both external libraries as well as classes from the project.

• Response for a Class (RFC). It is the count of all method invocations that happen in a class.

• Lack of Cohesion of Methods (LCOM). As the name suggests, it measures the lack of cohesion in a class. The idea behind the metric is to count the number of intersections between methods and attributes. The higher the number, the less cohesive is the class.

Code Smells

Still working on it...

Usage

usage: java -jar smellycat
 -arch <arg>          Architecture ('springmvc', 'android')
 -o,--output <arg>    Path to the output. Should be a dir ending with /
 -otype <arg>         Type of the output: 'csv', 'html'
 -p,--project <arg>   Path to the project

Version Comparison Extension

A -v option has been added to the API for version comparison. If included, The project directory must contain folders with different versions of the system. A sample project ( intro_android_demo) , API invocation -

-arch android -o smelout -otype html -p intro_android_demo -v

and output files ( smeloutresult.html, style_css.css) has been included.

Publications

TODO: list of publications here

References

• Alves, Tiago L., Christiaan Ypma, and Joost Visser. "Deriving metric thresholds from benchmark data." Software Maintenance (ICSM), 2010 IEEE International Conference on. IEEE, 2010.

• Chidamber, Shyam R., and Chris F. Kemerer. "A metrics suite for object oriented design." Software Engineering, IEEE Transactions on 20.6 (1994): 476-493.

License

This software is licensed under the Apache 2.0 License.