I believe that every one who are working on software development fields would have at least heard of the Gang of Four and their bible of design patterns - Design Patterns:. Elements of Reusable Object-Oriented Software Not to mention the ones who are going to learn design patterns. Most of them read this book for the starting point, and they may just start a tough road if they have not enough software design experience. Unfortunately, I was one of them. I took quite some time on finish reading this book , and I have got much from it. Even worse, I was completely confused by all those stuff. What I was still clear is some of the names of the patterns. Nothing else! I thought that's because I was lack of experience on software design PEOPLE LIKE ME, Are Not Ready for Learning Design Patterns. I Could Just Defer The Attempt Until I Got Enough Experience. I Had Believed this wishht for a long time.
On Day, The Book 'Design Patterns Explained: A New Perspective ON Object-Oriented Design' comes in Front of Me. I surprisingly Found That It Gives US A MUCH LOWER Threshold of Design Patterns Learning.
Pattern: a Solution to a problem in a context.
Basic Principles of od: 1. Design to Interface2. Favor Composition over Inheritance3. Find What Varies and Encapsulate IT
Compare and contrast the traditional way and the new way of looking at objects, encapsulation and using inheritance: 1.Objects: tra - as a bundle of data and methods new - as things with responsiblilities - focus on what the objects are supposed to do , not simply on how to implement them It makes object definition more flexible.2.Encapsulation:. tra - as hiding data new - as the ability to hide anything - gives a better way to split up the program.3.Inheritance: tra - For Specialization and Reuse New - As a Method of Classify Objects - Make It More Likely to Design To Interface.Handling Variation in Behavior with Objects.
Be aware of the relationship betWeen the: 1.CommonAlity / Variability Analysis2.The Conceptual, Specification and Implementation Perspectives3.an Abstract Class, ITS Interface and ITS Derived Classes
