In my main code, the variable created in the class is not found. What should I do to fix this?

Question

0.00/5 (No votes)

See more:

abstract class Shapes{
    public abstract double area();
    public abstract double perimeter ();
}
class Rectangle extends Shapes{
    private double width;
    private double length;
    public Rectangle(){
        this(1,1);
    }
    public Rectangle(double width, double length){
        this.width = width;
        this.length = length;
    }
    @ Override
    public double area(){
        return width * length;
    }
    @ Override
    public double perimeter(){
        return 2*(width + length);
    }
}


class Triangle extends Shapes{
    double a;
    double b;
    double c;
    public Triangle(){
        this(1,1,1);
    }
    public Triangle (double a, double b, double c){
        this.a = a;
        this.b = b;
        this.c = c;
    }
    @ Override
    public double area(){
        double s = (a+b+c)/2;
        return Math.sqrt(s*(s-a)*(s-b)*(s-c));
    }
    @ Override
    public double perimeter(){
        return a+ b + c;
    }
}
class Square extends Rectangle{
    Square s = new Square(50d);
    double area = s.area();
    double perimeter = s.perimeter();
}

public class Main
{
	public static void main(String[] args) {
	    width = 10;
	    length = 25;
	    Shapes Rectangle = new Rectangle (width, length);
	    System.out.println("The area of the rectangle is: " + Rectangle.area());
}
}

What I have tried:

I am a bit new to inheritance in java, and currently there is a problem where the variables I created in the classes aren't found in the main code. I tried making the variables in the rectangle class private however that did not work. What should I try doing?

Posted 12-Dec-22 4:12am

Aisha Yosuf

Updated 12-Dec-22 4:53am

v3

Add a Solution

2 solutions

Solution 2

This is your third question on this issue. I would suggest you spend some time at Java Tutorials Learning Paths[^].

Posted 12-Dec-22 4:53am

Richard MacCutchan

Add a Solution

Add your solution here

Treat my content as plain text, not as HTML

Preview 0

…

Existing Members

Sign in to your account

...or Join us

Download, Vote, Comment, Publish.

Your Email
Password
Forgot your password?

Your Email
This email is in use. Do you need your password?
Optional Password

I have read and agree to the Terms of Service and Privacy Policy
Please subscribe me to the CodeProject newsletters

When answering a question please:

Read the question carefully.
Understand that English isn't everyone's first language so be lenient of bad spelling and grammar.
If a question is poorly phrased then either ask for clarification, ignore it, or edit the question and fix the problem. Insults are not welcome.
Don't tell someone to read the manual. Chances are they have and don't get it. Provide an answer or move on to the next question.

Let's work to help developers, not make them feel stupid.

This content, along with any associated source code and files, is licensed under The Code Project Open License (CPOL)

CPallini · Accepted Answer · 2022-12-12T04:32:00

Replace

Quote:
public class Square extends Rectangle{
Square s = new Square(50d);
double area = s.area();
double perimeter = s.perimeter();
}

public class Main
{
public static void main(String[] args) {
width = 10;
length = 25;
Shapes Rectangle = new Rectangle (width, length);
System.out.println("The area of the rectangle is: " + Rectangle.area());
}
}

with

Java

class Square extends Rectangle
{
    public Square(int a){ super(a,a); }
}

public class Main
{
  public static void main(String[] args) 
  {
      int width = 10;
      int length = 25;
      Shapes rectangle = new Rectangle (width, length);
      Shapes square = new Square(width);
      System.out.println("The area of the rectangle is: " + rectangle.area());
      System.out.println("The area of the square is: " + square.area());

      int a = 12;
      int b = 20;
      int c = 15;

      Shapes triangle = new Triangle(a,b,c);
      System.out.println("The area of the triangle is: " + triangle.area());
      System.out.println("The perimeter of the triangle is: " + triangle.perimeter());

  }
}