Recommendations for how to do OOP design [closed]

Question

I find that whenever I begin writing an app in Java/C#, things start off good, but over time, as the app becomes more complex, it just gets more and more complicated. I've become aware of the fact that I'm not very good at design and high level architecture. All my classes become fairly strongly coupled and the design isn't "elegant" at all. I'm fairly competent at "low level" programming. That is, I can get just about anything done within a function or a class, but my high level design is weak and I'd really like to improve it. Does anyone have pointers to techniques, books, etc. that would be helpful in making me a better software engineer?

Answer 1

I disagree about starting with a book on design patterns or refactoring.

In my opinion, for a solid OO design, you should first be familiar with the main OO design principles, then understand how your problem can be represented in those basic principles. Then you can start discovering opportunities for applying design patterns and refactoring techniques in order to achieve those fundamental principles.

I would start with this book:

Agile Software Development, Principles, Patterns, and Practices by Robert C. Martin

In this book, Robert Martin describes the fundamental principles that make a good OO design, all of them related to encapsulation, coupling and modularity:

• The Open/Closed Principle
• Liskov Substitution
• Dependency Inversion
• Granularity
• Common Closure
• Reuse
• No Cyclic Dependency
• Stability Of Dependency
• Abstraction And Stability

After all, almost every Design Pattern and Refactoring technique I have seen documented in GoF and Fowler is aimed at achieving one of several of these basic principles, depending on their relative priority for a given scenario.

Answer 2

Books:

• Code Complete, by Steve McConnel
• Design Patterns, by Gamma, et. al.

Answer 3

I would start by sketching my design. That sketch could be a box and arrow diagram to show relationships between classes or it could be a variation on UML (or perhaps even standard UML). But I find that sketches help me see that a design is good/bad and maybe even how to fix it.

I would also look at a book on design patterns.