Abstraction Synonym 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: abstraction class

Sometimes we may come across a situation where we cannot provide implementation to all the methods in a class. We want to leave the  implementation to a class that extends it.   In that case we declare a class as abstract by using abstract keyword on method signature.In my framework I have created my PageBase class as super class of the all page classes.  I have collected all common elements and functions into PageBase class and all other page classes extent PageBase class. By doing so, I don't have to locate very common WebElements and it provides reusability in my framework. Also 1)Abstract classes cannot be instantiated 2)An abstarct classes contains abstract method, concrete methods or both. 3)Any class which extends abstarct class must   override all methods of abstract class 4)An abstarct class can contain either   0 or more abstract method.

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