Constructor Example Java Program


Definition

A constructor in a class is a special type of method called to create an object, It has the same name as that of the Class.

Constructor Types

  • Default Constructor
  • Parameterized Constructor
  • Private(SingleTon) Constructor

Constructor Characteristics In Java

  • A constructor has the same name of the Class
  • A constructor has no explicit return type
  • A constructor is called automatically, to create instance an object. 
  • A constructor must be the same as the name of the class.
  • Not like methods, constructors are not members of a class. we cannot call directly
  • A constructor can be overloaded.
  • A Constructor with no argument is called default Constructor
  • A Constructor with arguments is called Parameterized Constructor
  • Private Constructor is used for Singleton Class

Syntax

NameOfClass() {
    //Statements
    }

Syntax Example

Class Constructor {
	Constructor(){
		System.out.print("Its Called");
	}
}

Syntax Explanation

  • In the example, the name of the constructor is the same as that of the class name. When the constructor is executed, "I am inside default constructor" will be printed.

Constructor Example Program

class Constructor {
	Constructor() {
		System.out.println("I am inside default constructor");
	}
 
	public static void main(String[] args) {
		Constructor obj = new Constructor();
	}
}

Sample Output

Output is:
I am inside default constructor