CSE460 Lecture 10

Software Analysis and Design
Object-Oriented Principles
(202102)

Transcript

1. jgs CSE 460 Software Analysis and Design Lecture 10: Object-Oriented Principles Dr. Javier Gonzalez-Sanchez javiergs@asu.edu javiergs.engineering.asu.edu | javiergs.com PERALTA 230U Office Hours: By appointment
2. jgs Object-Oriented Principles Design
3. jgs 460 00001010 Key Concepts Encapsulation Abstraction Hierarchical Relationships Polymorphism Concurrency Persistency
4. jgs 460 00001010 Abstraction § Reducing by focusing on the essential observable behavior § What will be outside? OOAD, Booch Textbook
5. jgs 460 00001010 Encapsulation § Hiding the details of the implementation § What is inside? OOAD, Booch Textbook
6. jgs 460 00001010 Hierarchical Relationships § Creating a hierarchy of abstractions § Who (is a…, uses a…, has a…) ? OOAD, Booch Textbook
7. jgs 460 00001010 Polymorphism § The condition of denoting different forms. § A single name may denote objects of many different classes that are related by some common superclass. § When to use it?
8. jgs 460 00001010 Concurrency § Having two o more events happening (objects acting) at the same time. § When to use it? OOAD, Booch Textbook
9. jgs 460 00001010 Persistency § Property by which an object continues to exist even after its creator ceases to exist § Object serialization: convert it to a byte stream so way that the byte stream can be reverted into a copy of the object. § Save data OOAD, Booch Textbook
10. jgs Object-Oriented Principles Programming
11. jgs 460 00001010 Global Ideas § Create code Elegant and Efficient –Bjarne Stroustrup § Create code Simple and Direct –Grady Booch § Create code looks like written by someone who cares – Michael Feathers
12. jgs 460 00001010 Clean Code Principles § Readability Use Meaningful Names for Classes, Methods, and Variables Follow coding guidelines: e.g., read the Java Style Reference § KISS (Keep It Simple by K. Johnson) for your reader Small functions that do one thing § DRY (Do not Repeat Yourself): Avoid Code Bloat § Decoupling
13. jgs 460 00001010 Readability? § JFrame frmClient § JToggleButton btnNewButton § JLabel lblToggle § class MainWindow Create code Simple and Direct –Grady Booch Readability
14. jgs 460 00001010 Naming
15. jgs 460 00001010 DRY? Create code Elegant and Efficient
16. jgs 460 00001010 Where are the variables?
17. jgs 460 00001010 Readability Naming Review Language Guidelines
18. jgs 460 00001010 Readability Is the comment needed? Public vs Private?
19. jgs 460 00001010 Readability
20. jgs 460 00001010 Readability … … … 500 LOC in a method… it is to much!
21. jgs 460 00001010 How many LOC per method? § around 20 is perfect, § up to 50 is still fine, § up to 100 is critical, § above 150 is bad, and § more than 250 is !
22. jgs 460 00001010 Reference Chapter 2, 3
23. 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.