1. Software Metric Tools
Joel Keyser, Jacob Napp, Carey Norslien, Stephen Owings, Tristan Paynter

2. Overview SLF4J Tool Example Code Code Analyzer Linux Kernel JFreeChart
JUnit
SLF4J
SourceMonitor
JMetric
Metrics (Eclipse Plugin)
Understand

3. Libraries

4. JUnit Overview
Library used for creating, running, and sharing details of tests in Java
#1 used open source Java library
List of detailed features at

5. JFreeChart Overview
Library for creating graphs and other charts in Java applications
4.9/5 Stars on SourceForge download page
Easy to work with
Highly extensible

7. Linux Kernel Overview Operating system kernel for Linux.
Written in C, supported by GCC.
A kernel “manages input/output requests from software, and translates them into data processing instructions for the central processing unit and other electronic components of a computer” (Wikipedia)

8. SLF4J Overview Simple Logging Facade for Java
User can plug in desired logging framework at deployment
Research in 2013 sampled 10,000 java projects in GitHub and 30.7% of them used SLF4J.

9. OpenJDK7 Overview Open source implementation of Java Standard Edition
Officially supported by Oracle
Aided by community participation

10. Metric Tools

11. Code Analyzer (Desktop App)

12. Code Analyzer Overview
Free software
Simple to use
Supports
C (*.c, *.h)
C (*.cpp, *.cc, *.h, *.hh)
java (*.java)
html (*.html, *.htm)
Assembly (*.s, *.asm, *.ia)

13. Code Analyzer Metrics http://www.codeanalyzer.teel.ws/
Total Files (For multiple file metrics)
Total Lines
Code Lines
Comment Lines
Whitespace Lines
Average Line Length
Code Lines/File (For multiple file metrics)
Comment Lines/File (For multiple file metrics)
Code/Comments Ratio
Code/Whitespace Ratio
Code/(Comments + Whitespace) Ratio
Carey

14. Code Analyzer - jUnit

15. Code Analyzer - JFreeChart

16. Code Analyzer– Linux Kernel

17. SourceMonitor (Desktop App)
Jacob
SourceMonitor (Desktop App)

18. SourceMonitor Overview
Simple Software Metrics System
Free
Fully supports most of the common languages (C++, C, C#, VB.NET, Java, and Delphi)
Easy to use
Somewhat simplistic
Performance issues with large software projects, such as the Linux Kernel.

19. SourceMonitor Metrics
LOC
Percentage of Comments = (Lines w/ Comments) / LOC per class
Number of Branches per class
Max + Average depth per class
Max + Average Complexity per class

20. How Complexity is Determined
Determined by the number of execution paths through a function/method.
Starts with a base of 1
Add 1 for each branch (if, for, while)
Add 1 for each && or || in a logical condition
Add 1 for each exit from code (continue, break, throw, etc...)

21. Source Monitor Example – Linux Kernel
Entire Linux Kernel
Linux Kernel – arch
Carey
Linux Kernel – block

23. Joel
JMetric (Desktop App)

24. JMetric Overview
Software used to measure and display Object-Oriented metrics of other software
Specifically for Java
Can see the data in charts, tables*, or exported text files
Created in 1998 through the Swinburne University of Technology
Was last updated in 2000, hence the bugs
Fails to analyze most files
Various interface bugs

25. JMetric Metrics LOC, # variables, # methods Package Level Class Level
Lack of Cohesion of Methods (LCOM)
Class Level
Cyclomatic Complexity
# Parameters
# local variables
# if statements

26. Lack of Cohesion of Methods
BHS/CK/default are different ways to measure the same thing: the lack of cohesion per class
Low value is good (high cohesion), high value is bad (low cohesion)
Calculated by comparing the number of methods that share variables with the number of methods that do not
The point is that, ideally, all variables would be used by all methods

27. JMetric – JUnit Package Analysis

28. JMetric – JUnit Class Analysis

29. Metrics (Eclipse Plugin)
Phtephen
Metrics (Eclipse Plugin)

30. Metrics Overview Add-in to Eclipse Automatically calculates on build
For metrics that are “bad”
Shows resource most responsible
Allows easy fixing
Integrated directly into IDE

31. Metrics (Plugin) Metrics
Cyclomatic Complexity
Nested Block Depth
Steve

32. Metrics (Plugin) Metrics
Afferent Coupling
Efferent Coupling
Depth of Inheritance Tree
Tristan

33. Metrics - JFreeChart .equals method = 207 lines of if tests
.refreshTicksVertical = 190 lines of nested statements

34. Metrics - JUnit

35. JFreeChart – Number of Parameters
public LegendItem(String label, String description, String toolTipText, String urlText, boolean shapeVisible, Shape shape, boolean shapeFilled, Paint fillPaint, boolean shapeOutlineVisible, Paint outlinePaint, Stroke outlineStroke, boolean lineVisible, Shape line, Stroke lineStroke, Paint linePaint)

36. Understand

37. Understand Overview Static Code Analysis Tool
An IDE more concerned about analyzing a software project, rather than developing a software project.
Major Product Features
Code Knowledge
Metrics & Reports
Graphing
Standards Testing
Dependency Analysis
Doesn’t care about “good” or “bad” metrics.
Supports over a dozen languages, including C/C++/C# and Java.
Three price points
Floating License: $1,995
Single Developer License: $995.00
Free Two Week Trial

38. Understand Metrics Around 70 metrics Cyclomatic Complexity
Maximum Nesting Depth
Maximum Inheritance Tree

39. Comparison - Results

40. Comparison – SourceMonitor Metrics
Library
LOC
% Comments
% Branches/Class
SLF4J
26,538
46.0
11.9
Linux Kernel*
37,608
21.2
19.7
JUnit
677,058
17.4 5
JFreeChart
229,491
49.6
14.9
OpenJDK7
3,254,229
43.0
16.1
* Due to performance issues, only the block folder was analyzed.

41. Comparison – SourceMonitor Metrics
Library
Avg Depth/Class
Avg Complexity/Class
Number of Files
SLF4J
1.67
1.66
232
Linux Kernel*
1.53
3.69 75
JUnit
1.45
1,226,755**
8071
JFreeChart
1.96
2.38
653
OpenJDK7
2.54
1,359,640***
14,152
* Due to performance issues, only the block folder was analyzed.
** Two methods were measured with 1,936,482,677 complexity.
***Avg complexity varied widely.

42. Comparison – Plugin Metrics
Library
Cyclomatic Complexity
Nested Block Depth
Afferent Coupling
Efferent Coupling
Depth of Inheritance Tree
SLF4J
1.46
1.26
2.5
2.75
1.162
Linux Kernel* -
JUnit
1.265
1.213
12.18
4.557
1.361
JFreeChart
2.27
1.43
35.28
11.42
1.83
Open JDK7*
2.61
.82179
* Plugin only supports Java. Understand and Excel were used to obtain similar results.

43. Conclusion Metrics tools can be very useful for code analysis
Many different types of metrics tool, some open source other commercial
Tristan