CSE460 Lecture 33

Software Analysis and Design
Software Quality Metrics II
(202011)

Transcript

1. jgs CSE 460 Software Analysis and Design Lecture 33: Software Quality Metrics II Dr. Javier Gonzalez-Sanchez javiergs@asu.edu javiergs.engineering.asu.edu | javiergs.com PERALTA 230U Office Hours: By appointment
2. jgs Previously
3. Javier Gonzalez-Sanchez | CSE460 | Fall 2020 | 3 jgs Size Metrics § LOC – Lines of Code Metric. All lines that are not comments. Including lines of a single brace or parenthesis. § eLOC (effective Lines of Code) Metric. All lines that are not comments, blanks or standalone braces or parenthesis. § lLOC (logical Lines of Code) Metric. These statements are terminated with a semi- colon. The control line for the "for" loop contain two semi-colons but accounts for only one semi colon.
4. Javier Gonzalez-Sanchez | CSE460 | Fall 2020 | 4 jgs Understandability Metrics § Comment Percent = Comment Line Count / (LOC) x 100 § White Space Percentage = #spaces / (#spaces + #characters) * 100
5. Javier Gonzalez-Sanchez | CSE460 | Fall 2020 | 5 jgs Function Metrics Cyclomatic Complexity = Conditional_Nodes + 1 // CC = 3 + 1 = 4 (Condition nodes are 1,2 and 3 nodes) i = 0; n=4; while (i<n-1) { j = i + 1; while (j<n) { if (A[i]<A[j]) swap(A[i], A[j]); } i=i+1; }
6. jgs Test Yourselves
7. Javier Gonzalez-Sanchez | CSE460 | Fall 2020 | 7 jgs Code 1
8. Javier Gonzalez-Sanchez | CSE460 | Fall 2020 | 8 jgs Code 2
9. Javier Gonzalez-Sanchez | CSE460 | Fall 2020 | 9 jgs Code
10. Javier Gonzalez-Sanchez | CSE460 | Fall 2020 | 10 jgs Numbers LOC eLOC lLOC Cyclomatic Complexity m1 m2 m3 m4 m5 main Total
11. jgs Test Yourselves II
12. Javier Gonzalez-Sanchez | CSE460 | Fall 2020 | 13 jgs Example A § 3 files § 24 methods § 394 lines § 326 LOC § 285 eLOC § 182 lLOC § 20 Lcomments § Comments 5.1% § Blank lines 12.2% § Spaces: 21.0% (79% code) § Max CC: 6 § Average CC: 1.46 § 5 files § 21 methods § 522 lines § 412 LOC § 356 eLOC § 276 lLOC § 72 Lcomments § Comments 13.8% § Blank lines 7.3% § Spaces: 26.7% (73.3% code) § Max CC: 7 § Average CC: 2.24
13. Javier Gonzalez-Sanchez | CSE460 | Fall 2020 | 14 jgs Example
14. jgs Remember Structural Complexity
15. Javier Gonzalez-Sanchez | CSE460 | Fall 2020 | 16 jgs • Instability = Cout (Cin + Cout) Stable Abstraction Principle (SAP)
16. Javier Gonzalez-Sanchez | CSE460 | Fall 2020 | 17 jgs Distance § Distance: how far a package is away from the Main Sequence § D = A + I – 1 § Values -1 to 1 § Absolute Distance |D|
17. Javier Gonzalez-Sanchez | CSE460 | Fall 2020 | 18 jgs Example ITeamA = 6 / 0 + 6 = 1 ATeamA = 0 DTeamA = 0 + 1 – 1 = 0 IJlabel = 0 / 4 + 0 = 0 AJlabel = 0 DJlabel = 0 + 0 – 1 = -1 |Djlabel | = 1 Pain Zone (just an example!)
18. Javier Gonzalez-Sanchez | CSE460 | Fall 2020 | 19 jgs Stable Dependency Principle (SDP) § Every dependency between modules should terminate on a module whose Instability is less than or equal to the depending module's Instability. § Every dependency between modules should terminate on a module whose Abstractness is greater than or equal to the depending module's Abstractness.
19. Javier Gonzalez-Sanchez | CSE460 | Fall 2020 | 20 jgs Example MyNewClass OtherClass
20. jgs CSE 460 Software Analysis and Design Javier Gonzalez-Sanchez javiergs@asu.edu Fall 2020 Disclaimer. These slides can only be used as study material for the class CSE460 at ASU. They cannot be distributed or used for another purpose.