Object Oriented Programming - JAVA- Constructor

 

Object Oriented Programming - JAVA 👽

The constructor is the first thing that runs in a program. Is it true❓ You can answer this at the end of this discussion. 
Let's talk about constructor



Constructor...

A constructor is something that holds everything in the program. There are several features in this.
  • It is created by the name of the class
  • No return type is required
  • It's a method

           class Sun{
               Sun(){
                   // constructor
               }
               public static void main (String [] args){
                   Sun s = new Sun();
               }
           }

The constructor is executed when the object is called. The object is created in the main method. The object is executed by JVM(Java Virtual Machine). Constructor has two types. 

Parameter Less constructor

Here, we have no parameters (arguments) in the argument list.
           class Sun{
               Sun(){
                   // constructor
               }
               public static void main (String [] args){
                   Sun s = new Sun();
               }
           }

Parameterized constructor

In parameterized constructors , we have to put arguments to the argument list. This constructor parameter list also act as a parameter list and within the object the parameter list convert to argument list. we can pass the parameter values through the object.

           class Sun{
               Sun(int x, int y){
                   // constructor
               }
               public static void main (String [] args){
                   Sun s = new Sun(45,23);
               }
           }

Classes , constructors and object always belong to the object's variable.


Let's meet in the next blog to discuss about Method Overloading.


Comments

Post a Comment

Popular posts from this blog

Sorting Algorithms - JAVA👽

Image
 Sorting Algorithms - JAVA👽  Sorting algorithms are used to arrange data into a specific pattern (ascending or descending).We mainly discuss 5 patterns in this blog.  We can use any of this methods to sort an array. Selection sort Insertion sort Bubble sort Merge sort Quick sort  Selection sort ... Selection sort is well perform for small arrays and doesn't require extra temporary storage.  It uses selection method. It is poor to deal with huge list of items. It simple and easy to implement. It's time complexity is O(n^2) and space complexity is O(1). Here is the basic code for selection sort. for (int i=0; i< array.length-1; i++){             int curruntMinimum = i;             for (int curruntItem=i+1; curruntItem<array.length;curruntItem++){                 if(array[curruntItem] < array[curruntMinimum]){         ...
Read more

Object Oriented Programming - JAVA- class boundary, variable types, modifiers, java main method

Image
Object Oriented Programming - JAVA👽 There are certain aspects of Object Oriented Programming. So when we use OOP we need to know about those elements. In this blog, Let's discuss about class, variables, modifiers and methods & main method . Class.... A class is a blueprint that defines common variables and methods for objects of a particular type. A class has a boundary. Inside this boundary we only have the class, constructor and main method. Even if a method is in the class, we cannot take it to the class boundary. Variables.... Variables   are used to store information to be referenced and manipulated in a computer program. There are two variable types. Static variable Non - static variable Static variable The easiest way to find static variable is to find out if there is a static key ward.      ex :         static int i ; These can be accessed anywhere within the class. It can be accessed even without creating an object. Non - ...
Read more

Object Oriented Programming - JAVA- Method Overriding

Image
Object Oriented Programming - JAVA👽 Sometimes we have to fetch the same method name more than once. It is not possible in the programming process. But we can use method override to solve that error. So, in this blog we will discuss Method Overriding. Method overriding ... In a method inherited from a super class to a subclass, the process of changing the body is called as method overriding. So, To overriding the classes should inherit with one class to another class. Ex:   class Monkey{   void climb(){   sout ("Monkey climbs with their legs on jumping");   }    }   class Man extends Monkey{   void climb(){   sout ("Man climbs with using ladder");   }   } Here, above the subclass is the method of the superclass, and above that is the method of the subclass. That means, according to the example code,  The method of Man class is at the top The method of Monkey class is next The Man class is below the method o...
Read more