Java With Umer

This lesson is about the keyword final. You use the keyword final to make a variable constant so that it can be assigned a value only once. Variables are declared final be using the keyword final while declaring them. For example, final double PI=3.1416; In the above example, the PI is declared final and it … Read more Final (Lesson-31)

A class has methods and attributes. Any of them can be declared static using the static keyword. Normally, an attribute is declared like this (as we studied in previous lessons): public int size; A static one would look like this: public static int size; We are already using a static main method. A static method … Read more Static (Lesson-30)

A constructor is a special method in a class which is called automatically when an object of that class is created. It is used to initialize the newly created object. A constructor: is a method has exactly the same name as the class has no return type is not static Constructor can be used to … Read more Constructors (Lesson-29)

Getters and setters are methods inside your classes. They are declared to save the data inside a class from being accidentally modified. For each variable in the class, the getter method returns its value and the setter method sets its value. The name of a getter method starts with “get” followed by the variable name. … Read more Getters and Setters (Lesson-28)

For now, you all remember this: public static void main(String[] args) When you got your first lesson, you were told that you will study these things in detail in the upcoming lessons. Now let’s look at the parts of that statement from your first lesson: You have learnt about all the components except Access Modifiers … Read more Access Modifiers (Lesson-27)

Previously, you studied about creating classes and creating objects from those classes. But the class we took for an example contained only one method. Actually, the classes contain attributes and methods. Attributes are actually variables that reside in the class and are particular to the class and methods are methods which perform actions on those … Read more Class Attributes (Lesson-26)

In this lesson, we will learn how to create a new class in our java project and create objects from the class. This is the basis of Object Oriented Programming (OOP). Creating a new class in Netbeans Java project: 1. Right click the main package in your project. 2. Select New>>Java Class 3. In the … Read more Classes and Objects (Lesson-25)

In this lesson we will talk about methods which can get input and return output. Such methods are also called functions.They can take any number of inputs but return only one output. Input is given as parameters to the method and output is returned by the method itself. Previously, you studied the format of a … Read more Methods Part-2 (Lesson-24)

When solving a complex problem, it becomes necessary to break down the problem into small parts and solve those parts separately. This is where the concept of methods and Object Oriented Programming (OOP) comes in. For this lesson, we will concentrate on methods only. A method is a set of statements that can be used … Read more Methods Part-1 (Lesson-23)

An array of arrays is called a multidimensional array. Let’s start with a simple two dimensional array. A two dimensional array is defined as follows: DataType[][] arr; For example: int[][] iArray; To initialize a multidimensional array, place each array within its own set of brackets: int[][] iArray={ {2,3,6} , {6,2,9} }; The above array is … Read more Multidimensional Arrays (Lesson-22)