Question

The following code is for a class named Box. The class Box includes a constructor method Box, and a method getVolume().

For your assignment you are to develop a java class named MatchBox. Your class MatchBox must extend the class Box and in addition to the attributes width, height, and depth that are defined in the class Box, MatchBox must add a new attribute weight. The getVolume method must both report the values of width, height, depth, and weight, but must also calculate and report the volume by multiplying height by width by depth. The class MatchBox must also add the method calculateWeight() that will calculate weight based upon the volume assuming that the volume is a quantity of water which weighs .03611 pounds per cubic inch. Also method calculateWeight should show the result like this: weight of MatchBox is X.

For example a car class can inherit some properties from a General vehicle class. Here we find that the base class is the vehicle class and the subclass is the more specific car class. A subclass must use the extends clause to derive from a super class which must be written in the header of the subclass definition. The subclass inherits members of the superclass and hence promotes code reuse. The subclass itself can add its own new behavior and properties.

Your new class must include a main method that creates a new MatchBox object, calls the getVolume method and reports the results by printing the following items to the screen (where the X is replaced by the calculated value) For your assignment, assume that the value of width is 5, height is 10, and the depth is 3. The output should look like the following with X replaced with the appropriate calculated value.

width of MatchBox is X
height of MatchBox is X
depth of MatchBox is X
weight of MatchBox is X
Volume is: X

Helpful Hints

When creating this assignment you should assume a java file for each component. First create a Box.java to hold the box class, a MatchBox.java for the MatchBox class and a main.java for the main routine. All three files, when using Netbeans must belong to the same package so make sure you use the package statement at the beginning of each file.

Keep in mind that in the new class MatchBox, you can either use the methods and variables in the Box class, redefine methods or variables for the MatchBox class that exist in Box or create new methods and variables.

======

The class Box is as follows:

class Box {
 
   double width;
   double height;
   double depth;
 
   // This is an empty constructor
   Box() {
          ;
   }
 
   Box(double w, double h, double d) {
          width = w;
          height = h;
          depth = d;
   }
 
   void getVolume() {
          System.out.println("Volume is : " + width * height * depth);
   }

Answer 1

class Box{ }// this the class box
  
double width;
double height;   
double depth;
public Box() // constructor of class box
{
}
public Box(double w,double h,double d) // Constructor of class box with parameter
{
width=w;
height=h;
depth=d;
}
public void getVolume(){ // method getvolume will print the volume
System.out.println("Volume is:"+width*height*depth);
}
}
class MatchBox extends Box { // subclass of box is matchbox
double weight;

public MatchBox(double w, double h, double d) { // constructor of matchbox
super(w, h, d); // it is used to call base class constructor
}

public double calculateWeight() { // method calculateweight
weight = (width * height * depth) * 03611;
return weight;   
}

public void getVolume() { // overloading getvolume method
System.out.println("width of MatchBox is: " + width);
System.out.println("height of MatchBox is: " + height);
System.out.println("depth of MatchBox is: " + depth);
System.out.println("weight of MatchBox is: " + weight);
}
}
public class Main {

public static void main(String[] args) {

MatchBox matchbox = new MatchBox(5, 10, 3); // creating object of matchbox class
matchbox.calculateWeight(); // calling the method calculateweight of matchbox class
matchbox.getVolume(); // calling method getvolume of matchbox class
Box box = new Box(5, 10, 3); // creating object of box class
box.getVolume(); // calling the method getvolume of box class
}
}