Design Patterns - Re-use, dont re-invent the wheel!!

Long time since I had done any note on Technical stuffs... It is always an easy but risky thing to write something technically, the very reason being, we gonna write something which is rite there very much existing.. Since it is existing, no need to add any spicy masala, juicy jigar thanda to it... Just write as-is... Sametime, any inaccuracy would be a 'digging a perfect my own grave' on this topic..

Before I start sharing of what I know in Design patterns, I would like to give the due tribute to the great techy tutor, one of the great teachers of my time I believe - Mr. Shabarinath KP who gave me the exact of know-what of Design Patterns... I am sure 80% of this Design Patterns blog would be from the notes I had taken from his classroom session!! And the other 20% would be my grammer mistakes!!

Ok, no more big fun, babool, boomer drags... Lets get straight in DP matters...

First, before getting to know 'about' anything, it is always a good 'practice' that we get to know why do we need that! So, lets see 'why' design patterns before hopping to 'How' of the D patterns.

My dad is a seasoned mechanic in motor cars and he is passionate on repairing them. (No, no, he is not a Khan, he can repair only Motor cars and bikes). During the 80's our business flourished like anything... In the mid 90's the business started taking a little deceleration, but it was not seamingly visible. In the 21st century, the business almost taking a reverse gear...

The very reason for this downfall is not only the recent recessions and blah blah.. The simple and subtle cause is almost all the Motor Cars manufacturers offer the AMC (Annual Maintenace contract) at a reasonable rate. So any customer (that may include me as well - sorry dad), who has bought the car for a mountain price, would always, 20 out 22 times, prefer for getting serviced, repaired in the authorized repairing/service centre and definitely not the risk of going to some unknown mechanics!

So, why do we need to go for an authorized Service centre instead of a local craftsman? - Reason is the standards, it is well known for Authorized Centre's practices (or atleast the look-alike ;-)) and most importantly, it is proven... We still believe Sachin IS the best even if he delivers an HatTrick of Golden ducks...

This exactly the same reason, why do we need to go for Design Patterns. Its a kind of just re-using the wheel instead of re-inventing it... (ahh., the title is now used... ;-)). So DP has its standards, best practices and most most importantly, its tested, tested and tested and proven to be error proof, if used appropriately and correctly...

The term 'appropriately' mentions whether a particular problem could be fixed/approached/achieved by DP. The instance 'correctly' denotes the usage of the guidelines correctly and as per the stated (and tested/proven) 'rules'...

So, as per the 'text book' definition, "Design patterns are documented, tried and tested solutions for recurring problems in a given context".

So another very nice and hi-fi requirement for the DP is that it makes the visualization of the architecture more simple and efficient. One can clearly and quickly snap the HLD (High Level Design) when seeing a particular problem...

Fine.. Thats tooo much of 'Y' about DP... Lets explore the patterns of design in detail hereon!!

Cheers!!!