Studying design patterns helps a software developer get the big picture - from a designer's perspective. Knowing the common design patterns enables us to understand how different parts of the software are related to each other. Not only this, but knowledge of design patterns helps to communicate with other developers in a more object-oriented way.
Let me give you an example.
You know callback mechanism, observer pattern, and event listener pattern - all do kind of the same work - notify some objects when a specific event occurs. However, without the knowledge of design patterns, we will simply try to understand this phenomenon from just a programmer's point of view - and definitely, we will miss the big picture behind writing such kinds of object-oriented code.
I remember, when I studied the command routing architecture of Visual C++/MFC source code, I tried to map it with the Gang of Four design patterns and found out that this architecture uses two common design patterns at the same time - Command pattern and Chain of responsibility pattern.
Studying design patterns helps to decipher object-oriented code more like a professional - and not like a novice programmer.
It helps to figure out the source code not only from what and how's point of view, but also from Why's point of view. We can explain why a piece of code has been or should be written in a particular way.
Understanding the Why's is very essential for a software developer.
Let me tell you about my journey in NOKIA India in 2007 using Symbian S60 C++ framework.
There is a concept in Symbian called a two-phase constructor. I asked people about the Why's point of view. Nobody gave me the answer - everybody said this is the norm in Symbian. While breaking my head about this "why", I went to Japan and then realized the reason for such a two-phase constructor - to avoid the exception during constructor in case of low memory. Because in the earlier days of mobile phones, there was limited memory and moreover there were no template concepts in C++. Hence there was no smart pointer. This led me to study Boost pointer in Japan in 2008 and voila, in 2009 Boost library became a part of the standard C++ library.
In concisely, to get the big picture of any object-oriented code structure, it's important to know Design Patterns. It clarifies many questions - particularly why a piece of code should be written in a specific manner.
Here's the evolutionary journey of Ridit, my son and a young Computer Scientist of Bharat - vis-a-vis Design Pattern...
My bragging right - as a Guru of my son...
State Pattern in Java : 8 yrs old
State pattern in C++ : 11 yrs old
State pattern in Python : 12 yrs old
