Using Constructors & Member Function to add two numbers: Java

In this Java video tutorial we have covered both ways of adding numbers: using constructors as well as using methods.

Constructors:

Constructor name and the class name must be same.
No return type.
There are 3 types of constructors:
1. Default constructors.
2. Parameterized constructors.
3. Copy Constructors.

In this video tutorials we have shown the use of Parameterized constructors.

 calc(int a, int b)
 {
  no1 = a;  
  no2 = b;  
 }

Adding and displaying the result:

 public void sum()
 {
  System.out.println("Sum of "+no1+" and "+no2+" is "+(no1+no2));
 }

Strings are written inside double quotes and the variables written outside the double quotes will display the value stored in them.
+ (plus) is concatenation operation.
(no1+no2) adds the value present in no1 and no2 and displays the result of addition.

Video Tutorial



YouTube Link: https://www.youtube.com/watch?v=gUXq1psurdk [Watch the Video In Full Screen.]



Object Creation:

/* calc c;   // object declaration. It will have null in it.
   c = new calc(20,10); // Construction call
*/ 
   calc c = new calc(30, 10);

Full Java code: Using Constructors & Member Function to add two numbers(add.java)

import java.lang.*;

class calc
{
 int no1, no2;
 
 calc(int a, int b)
 {
  no1 = a;  // 30
  no2 = b;  // 10
 }

/*
 public void assign(int a, int b)
 {
    no1 = a;  // 30
                  no2 = b;  // 10
 } 
*/ 
 public void sum()
 {
  System.out.println("Sum of "+no1+" and "+no2+" is "+(no1+no2));
 }
}

class add
{
 public static void main(String args[])
 {
  /* calc c;   // object declaration. It will have null in it.
  c = new calc(20,10);  // Construction call
  */  
  calc c = new calc(30, 10);
  //c.assign(30,10);
  c.sum();
 }
}

Member functions are called with the help of object.
Syntax:
object.memberfuntion();