CSC305 Lecture 02

Individual Software Design and Development
Clean Coding
(202501)

Transcript

1. Dr. Javier Gonzalez-Sanchez javiergs@calpoly.edu www.javiergs.info o ffi ce: 14 -227 CSC 305 Individual Software Design and Development Lecture 02. Clean Coding
2. Clean Coding • Write e ff icient code but prioritize re a d a bility a nd m a int a in a bility. • Optimize perform a nce-critic a l sections only when necess a ry. 2
3. Manufacturing vs. Crafting
4. Clean Coding Single Responsibility Principle (SRP) Do not Repeat Yourselves (DRY) Keep It Simple (KIS) Error Handling Readability (Easy to read to others) Style and Comments Dependency Injection (DI)
5. Style and Comments
6. Consistent Formatting • Follow a consistent code style a nd form a tting guidelines. https://google.github.io/styleguide/javaguide.html • Use indent a tion, whitesp a ce, a nd comments e ff ectively to enh a nce re a d a bility. 6
7. Meaningful Names • Use descriptive a nd un a mbiguous n a mes for v a ri a bles, functions, cl a sses, etc. • Avoid using misle a ding or cryptic n a mes. • Follow consistent n a ming conventions. 7
8. Commenting and Documentation • Write me a ningful comments th a t expl a in why something is done, not wh a t is done. • Keep comments up to d a te with code ch a nges. • Document public APIs a nd complex logic thoroughly. • Single Line vs Multiple Line ( a nd J a v a Doc) comments 8
9. Code 9 https://github.com/CSC3100/App-Paint/
10. Code 10 https://github.com/CSC3100/App-Paint/
11. DRY
12. Don't Repeat Yourself (DRY) • Avoid code duplic a tion by a bstr a cting common function a lity. • Use functions or cl a sses to enc a psul a te repe a ted jobs. 12
13. KIS
14. Keep It Simple (KIS) • Aim for simplicity in your design a nd implement a tion. • Avoid unnecess a ry complexity or over-engineering. 14
15. Code 15 https://github.com/CSC3100/App-Paint/
16. Code 16 https://github.com/CSC3100/App-Paint/
17. Single Responsibility
18. Single Responsibility • E a ch cl a ss or function should h a ve one, a nd only one, job. • Keep functions focused on a single t a sk. • Bre a k down your code into sm a ller, reus a ble modules or functions. • Ensure e a ch module or function h a s a cle a r, well-de f ined purpose. • 18
19. Example 19
20. Some Ideas. It is NOT a Complete List 20 MOVE EAT SHOW DETECT COLLISION MOVE/ HUNT SHOW SHOW/ CREATE SCORE HANDLING WINNER DETECTOR MOVE/ HUNT
21. Tic Tac Toe 21 Main Player Game
22. Tic Tac Toe 22 Main Player GameEngine GameBoard
23. Tic Tac Toe 23 Driver Player Game public class Driver { public static void main(String[] arg) { Player player = new Player(); Game game = new Game(); game.ready(); do { player.move(); game.move(); } while (!game.isOver()); game.bye(); } }
24. Dependency Injection
25. Dependency Injection • An object’s dependencies (other objects it relies on) a re provided extern a lly r a ther th a n cre a ted intern a lly by the object itself. • Constructor injection: Dependencies a re p a ssed vi a the cl a ss constructor. • Setter injection: Dependencies a re provided through setter methods. • M a ke components more a ccessible to sw a p or extend without modifying the dependent cl a ss. 25
26. Dependency Injection What about text-based vs. GUI?
27. Tic Tac Toe 27 Main Player Game View
28. Dependency Injection 28 public class Driver { public static void main(String[] arg) { View view = new View (); Player player = new Player(view); Game game = new Game(view); game.ready(); do { player.move(); game.move(); } while (!game.isOver()); game.bye(); } }
29. Dependency Injection 29 public class Driver { public static void main(String[] arg) { View view = new View (); Player player = new Player(view); Game game = new Game(view); game.ready(); do { player.move(); game.move(); } while (!game.isOver()); game.bye(); } } public class View { public void print(String s) { System.out.println(s); } } public class Game { View myView; public Game(View v) { myView = v; } public void ready() { myView.print (“Welcome!”); } // more code … }
30. Questions 30
31. Lab 01
32. Apply these Single Responsibility Principle (SRP) Do not Repeat Yourselves (DRY) Keep It Simple (KIS) Error Handling Readability (Easy to read to others) Style and Comments Dependency Injection (DI)
33. Lab 02 (Quiz)
34. Quiz (45 minutes - 15 questions) Let’s Test Your Java Programming
35. CSC 305 Individual Software Design and Development Javier Gonzalez-Sanchez, Ph.D. javiergs@calpoly.edu Winter 2025 Copyright. These slides can only be used as study material for the class CSC305 at Cal Poly. They cannot be distributed or used for another purpose.