I need help creating a Rectangle class with private instance variables, but public methods and constructors

Question

I'm new to using java and I need to make a class called Rectangle, but the code I'm using doesn't seem to work, and the notes for class aren't helpful. I feel like it has something to do with my methods because I don't understand those too well.

The class needs to follow these requirements: Create a class called rectangle with the following instance variables and public constructors:

• width, double

• height, double

• a constructor with one parameter (double) called sideLength, which sets both the width and height to sideLength.

• a constructor with two parameters width and height (double), which sets both the width and height to the corresponding values that are passed on.

• a public method computeArea with no parameters that returns the area of Rectangle as a double

• a public method computePerimeter with no parameters that returns the perimeter of Rectangle as a double

• a public method getHeight with no parameters that returns the height of Rectangle as a double

• a public method getWidth with no parameters that returns the width of Rectangle as a double

I don't need to make a main method because that was already provided.

This is the code that I'm using, but I keep getting an error that says height cannot be found from the computeArea method and down.

 class Rectangle{
     
     private static double width;
     private static double heigth;
     
     public Rectangle(double sideLength) {
         
         Rectangle width = new Rectangle(sideLength);
         Rectangle height = new Rectangle(sideLength);
     }
         
     public Rectangle(double width, double height){
         width = width;
         height = height;
     }    

     public double computeArea() {
         return height * width;
     }
         
     public double computePerimeter() {
         return 2 * (height + width);
     }
         
     public double getHeight() {
         return height;
     }
     
     public double getWidth() {
         return width;
     }
     
 }

Answer 1

Don't make the private variables static or they will be shared by all instances of Rectangle.

class Rectangle{
     
     private double width;
     private double height;
     
     public Rectangle(double sideLength) {
         
         this.width = sideLength;
         this.height = sideLength;
     }
         
     public Rectangle(double width, double height){
         this.width = width;
         this.height = height;
     }    

     public double computeArea() {
         return height * width;
     }
         
     public double computePerimeter() {
         return 2 * (height + width);
     }
         
     public double getHeight() {
         return height;
     }
     
     public double getWidth() {
         return width;
     }
 }

To use it in other code:

public class Test {
  public static void main(String[] args) {
    Rectangle square = new Rectangle(1.0);
    double area = square.computeArea();
    System.out.println(area);
    Rectangle rectangle = new Rectangle(1.0, 2.0);
    area = rectangle.computeArea();
    System.out.println(area);
  }
}