Java Program to Allocate and Initialize Super Class Members Using Constructor

// Parameterized Constructor Example in Java

import java.io.*;
class parameterizedConstructor {

    // fields of the class
    String name;
    int regestrationNumber;

    // creating a parameterized constructor so that we can
    // initialize the value of the class
    parameterizedConstructor(String name,
                             int regestrationNumber)
    {
        System.out.println("constructor call");
        this.name = name;
        this.regestrationNumber = regestrationNumber;
    }
}

class GFG {
    public static void main(String[] args)
    {
        // creating our first object
        parameterizedConstructor obj1
            = new parameterizedConstructor("Nilesh",
                                           2021806);
        System.out.println("Name of the student "
                           + obj1.name);
        System.out.println("Registration Number "
                           + obj1.regestrationNumber);

        // creating second object
        parameterizedConstructor obj2
            = new parameterizedConstructor("Bhaskar",
                                           2021807);
        System.out.println("Name of the student "
                           + obj2.name);
        System.out.println("Registration Number "
                           + obj2.regestrationNumber);
    }
}

// Java Program to Allocate and Initialize Super Class
// Members Using Constructor

import java.util.*;
class y {
    int b;
    int c;

    // parameterized constructor of class y
    y(int b, int c)
    {
        this.b = b;
        this.c = c;
        System.out.println("Hi I am parent constructor");
        System.out.println("multiplication of two number "
                           + b + " and " + c + " is "
                           + b * c);
    }
}
class x extends y {
    int a;

    // parameterized constructor of class x
    x(int b, int c, int a)
    {
      
          // calls constructor of y
        super(b, c);
        System.out.println(
            "Hi I am child class constructor");
        System.out.println("class field of x class is "
                           + a);
    }
}

class GFG {

    public static void main(String[] args)
    {
        // creating an object of class x
        // this will invoke the constructor of x
        // but before invoking the constructor of class x
        // it will invoke the constructor of it's parent
        // class which is y
        x obj = new x(3, 4, 5);
    }
}

// Java Program to Allocate and Initialize Super Class
// Members Using Constructor

import java.io.*;
class grandParent {
    int grandParentAge;
    String grandParentName;

    // constructor
    grandParent(int grandParentAge, String grandParentName)
    {
        this.grandParentAge = grandParentAge;
        this.grandParentName = grandParentName;
    }
}
class parent extends grandParent {
    int parentAge;
    String parentName;

    // parameterized constructor
    parent(int grandParentAge, String grandParentName,
           int parentAge, String parentName)
    {
      
          // calls grandparent constructor
        super(grandParentAge, grandParentName);
        this.parentAge = parentAge;
        this.parentName = parentName;
    }
}
class child extends parent {
    int childAge;
    String childName;
  
      // constructor
    child(int grandParentAge, String grandParentName,
          int parentAge, String parentName, int childAge,
          String childName)
    {
      
          // calls parent constructor
        super(grandParentAge, grandParentName, parentAge,
              parentName);
        this.childAge = childAge;
        this.childName = childName;
    }
    public void dispalyDetails()
    {
        System.out.println("Name of grand parent "
                           + grandParentName + " and he is "
                           + grandParentAge + " year old");
        System.out.println("Name of parent " + parentName
                           + " and he is " + parentAge
                           + " year old");
        System.out.println("Name of child " + childName
                           + " and he is " + childAge
                           + " year old");
    }
}
class GFG {
    public static void main(String[] args)
    {
        // creating an object of class child
        // this will invoke the constructor of child
        // but before invoking the constructor of class
        // child it will invoke the constructor of it's
        // parent class which is parent but parent is child
        // of grandparent class so, before invoking the
        // constructor of parent class it will invoke the
        // constructor of grandparent class
        child obj = new child(85, "Pan Singh", 39,
                              "M.S.Dhoni", 5, "Ziva Dhoni");
        obj.dispalyDetails();
    }
}