Java Encapsulation

Java Object Oriented Programming Concepts, Java Inheritance Types of Inheritance, Java Polymorphism, Method OverLoading, Method Overriding, Java Abstraction, Java Interfaces and Java Encapsulation.
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Gowtham Ramesh
Posts: 66
Joined: Thu Nov 22, 2018 5:23 am

Java Encapsulation

Post by Gowtham Ramesh » Tue Nov 27, 2018 11:31 am

What is the usage of Java Encapsulation in Selenium Automated Testing?

AyubHussain
Posts: 142
Joined: Fri Nov 23, 2018 2:48 am

Re: Java Encapsulation

Post by AyubHussain » Wed Dec 05, 2018 11:06 am

Encapsulation is defined as the wrapping up of data under a single unit. It is the mechanism that binds together code and the data it manipulates.Other way to think about encapsulation is, it is a protective shield that prevents the data from being accessed by the code outside this shield.

1) Technically in encapsulation, the variables or data of a class is hidden from any other class and can be accessed only through any member function of own class in which they are declared.
2) As in encapsulation, the data in a class is hidden from other classes, so it is also known as data-hiding.
3) Encapsulation can be achieved by: Declaring all the variables in the class as private and writing public methods in the class to set and get the values of variables.

// Java program to demonstrate encapsulation
public class Encapsulate
{
// private variables declared
// these can only be accessed by
// public methods of class
private String geekName;
private int geekRoll;
private int geekAge;

// get method for age to access
// private variable geekAge
public int getAge()
{
return geekAge;
}

// get method for name to access
// private variable geekName
public String getName()
{
return geekName;
}

// get method for roll to access
// private variable geekRoll
public int getRoll()
{
return geekRoll;
}

// set method for age to access
// private variable geekage
public void setAge( int newAge)
{
geekAge = newAge;
}

// set method for name to access
// private variable geekName
public void setName(String newName)
{
geekName = newName;
}

// set method for roll to access
// private variable geekRoll
public void setRoll( int newRoll)
{
geekRoll = newRoll;
}
}

In the above program the class EncapsulateDemo is encapsulated as the variables are declared as private. The get methods like getAge() , getName() , getRoll() are set as public, these methods are used to access these variables. The setter methods like setName(), setAge(), setRoll() are also declared as public and are used to set the values of the variables.

The program to access variables of the class EncapsulateDemo is shown below:

public class TestEncapsulation
{
public static void main (String[] args)
{
Encapsulate obj = new Encapsulate();

// setting values of the variables
obj.setName("Harsh");
obj.setAge(19);
obj.setRoll(51);

// Displaying values of the variables
System.out.println("Geek's name: " + obj.getName());
System.out.println("Geek's age: " + obj.getAge());
System.out.println("Geek's roll: " + obj.getRoll());

// Direct access of geekRoll is not possible
// due to encapsulation
// System.out.println("Geek's roll: " + obj.geekName);
}
}

Advantages of Encapsulation:

Data Hiding: The user will have no idea about the inner implementation of the class. It will not be visible to the user that how the class is storing values in the variables. He only knows that we are passing the values to a setter method and variables are getting initialized with that value.

Increased Flexibility: We can make the variables of the class as read-only or write-only depending on our requirement. If we wish to make the variables as read-only then we have to omit the setter methods like setName(), setAge() etc. from the above program or if we wish to make the variables as write-only then we have to omit the get methods like getName(), getAge() etc. from the above program

Reusability: Encapsulation also improves the re-usability and easy to change with new requirements.
Testing code is easy: Encapsulated code is easy to test for unit testing.

sekhar
Posts: 47
Joined: Mon Dec 31, 2018 6:40 am

Re: Java Encapsulation

Post by sekhar » Tue Jan 22, 2019 12:03 pm

Encapsulation in Java is a mechanism of wrapping the data (variables) and code acting on the data (methods) together as single unit. In encapsulation the variables of a class will be hidden from other classes, and can be accessed only through the methods of their current class, therefore it is also known as data hiding.

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