title: Class hierarchy of shapes
body: <p>Hello I have these classes in my Java exercise: <code>Rectangle</code> and <code>Ellipse</code>. Is <code>Square</code> child of <code>Rectangle</code> or should I make special constructor?</p>
  
  <pre><code>// constructor for Square
  public Rectangle(double side) {
      this.width = side;
      this.height = side;
  }
  </code></pre>
  
  <p>Is <code>Circle</code> child of <code>Ellipse</code> (<code>extends</code>)?</p>
  
  <p>This could be a simple application like Kojo or Geogebra.</p>