oop abstraction code example

Example 1: what is abstraction

it is process of hiding implementation details and 
only showing the functionality to the user. 
Abstraction focus on what the object does instead of how it does. 
It is achieved by using Abstract class and Interface. 
abstract methods (methods without body, cannot be static and final), 
interface must implemented and abstract classes must be extended 
by regular classes in order to achieve abstraction 
(because abstract methods can only be exist in abstract class and interface). 
A class can implement multiple interfaces, 
but it can extend only single abstract class.

Ex: In my framework I have achieve abstraction by using collections or 
Map, because it’s all interface. Most of the cases I come across using List. 
If we want to access elements frequently by using index, List is a way to go. 
ArrayList provides faster access if we know index. 
If we want to store elements and want them to maintain an order, 
List is a better choice.

i)List<String> webs=driver.getWindowHandles();
=>create a list first to store web URLs in list

ii)findElements evaluates multiple elements so therefore will assigned 
to List <WebElement>

iii)To handle dynamic elements store it in the list and identify by index:
List<WebElement> all=driver.findElements(By.tagname(“”)); (or other locators).

Example 2: method abstraction

// Method abstraction is the practice of reducing inter-dependency between methods.  
 // The following is an unreasonably simple example, but the point stands: 
 // don't make the person on the other side of your function do more work 
 // than they need to.  Include all necessary data transformations in your 
 // methods as is.  For instance, take method GetAreaOfCircle: 

 // Good practice: 
float GetAreaOfCircle(float radius) {
	return 3.14f * radius * radius;
}
int main() {
	printf("%d", GetAreaOfCircle(3.0f));
    getch();
    return 0;
}

 // Bad practice: 
float GetAreaOfCircle(float radius) {
	return radius * radius;
}
int main() {
	float area = 3.14f * GetAreaOfCircle(3.0f);
	printf("%d", );
    getch();
    return 0;
}