Atomicity: you have likely seen “nonatomic” in property declarations numerous times. When you declare a property as atomic, you usually wrap it in a @synchronized block to make it thread safe. Of course, this approach does add some extra overhead. To give you an idea, here is a rough implementation of an atomic property:
// If you...
Tuesday, December 31, 2013
NSAutoreleasePool in iOS / why NSAutoreleasePool needed ?
NSAutoreleasePool:-
The NSAutoreleasePool class is used to support Cocoa’s reference-counted memory management system. An autorelease pool stores objects that are sent a release message when the pool itself is drained.
Why NSAutoreleasePool is needed?:-
To minimize the peak memory footprint. Use in block of code when you feel that...
Thursday, December 19, 2013
Bridge pattern - Structural Design Pattern
Bridge Pattern
Bridge Pattern
Ref:-
http://www.tutorialspoint.com/design_pattern/bridge_pattern.htm
http://www.codeproject.com/Articles/42762/Bridge-Design-Pattern
Its a structural design pattern.
Just like how printers work with computers. If we have a USB...
Wednesday, December 18, 2013
Adapter pattern - Structurel pattern
Adapter Pattern
Adapter design pattern allows you to make an existing class work with other existing class libraries without changing the code of the existing class.
Maximum times we needed that methods of the existing class should work with other existing class...
Prototype pattern - Creational Design Pattern
Prototype Pattern
Its a creational design pattern. Its normally used to create duplicate objects. This pattern is used normally when the creation of object is costly. Example:- Object created and have lots of expensive operation like sql query etc When next...
Builder Design Pattern - Creational Design Pattern
Builder Pattern
Ref:- http://www.tutorialspoint.com/design_pattern/builder_pattern.htm
Its creational design pattern.
Builder pattern builds a complex object using simple objects and using step by step approach. The builder is independent of other objects.
Example:-
This...
Singleton Design Pattern - Creational Design Pattern
Singleton Design Pattern
Its creational design pattern. Singleton pattern is to ensure that a class has only one instance and provides global point of access it.
Implementation
Singleton class have its constructor as private and have static instance of itself. Class...
Abstract Factory Pattern - Creational design pattern / Abstract Factory tutorial / Abstract Factory example
Abstract Factory Pattern
Its a creational design pattern. It's extension to factory method. It creates more level of abstraction to factory (factory method) so called Abstract Factory Pattern. This factory is also called as Factory of factories. In this interface...
Factory method design pattern - Creational design pattern
Factory method
Its a Creational design pattern.
Definition: “The factory pattern is used to replace class constructors, abstracting the process of object generation so that the type of the object instantiated can be determined at run-time.”
Define an interface for...
Tuesday, December 17, 2013
Design pattern tutorial / Design pattern with example / Design pattern fundamentals / Creational Design Patterns / Structural design Patterns / Behavioral design pattern
Design pattern
Design pattern is a general repeatable solution to a
commonly occurring problem in object-oriented software design.
its like library of solution to desired
problem. These solutions were obtained
by trial and error by numerous software developers over quite a substantial
period of time. Design...
