Visualforce - Beyond Basics Series 7 - Controller polymorphism using init action

What is Constructor Polymorphism ?

It's the method of initializing a object differently based on different context. This is achieved though init action in the page tag.

When it is useful ?

In many cases, you need to share the controller, extension between different pages/components. But, it wont be possible if the object is initialized with default set of values. So, you may need to initialize the object very differently for different cases.

Where is the code ?

I have a Class in Apex which will be shared among two pages. These pages will initialize the object differently. This is just a basic case, but, it could initialize or perform certain logic & make the object look entirely different.