public static void main(String[] args) { Object[] objects = {new Triangle(5, 5), new Square(3), new Circle(3)}; // compute areas for (Object o : objects) { if (o instanceof Triangle) { Triangle t = (Triangle) o; System.out.println(t.computeArea()); } if (o instanceof Square) { Square s = (Square) o; System.out.println(s.computeArea()); } if (o instanceof Circle) { Circle c = (Circle) o; System.out.println(c.computeArea()); } } }
// App class constructor public App() { // Print out a test message to the console to confirm running program // Uses java.lang library System.out to do priting to console System.out.println("App constructor success!"); // Delare and instantiate objects MainWindow myWindow = new MainWindow(); InputBox inBox = new InputBox(myWindow); OutputBox outBox = new OutputBox(myWindow); // Render the main window myWindow.show(); // Declare and initialise variables to default values double baseDimension = -1; double heightDimension = -1; double area = -1; // Get input form the user baseDimension = inBox.getDouble("Please enter the size of the base in mm: "); heightDimension = inBox.getDouble("Please enter the height in mm: "); // Debug output System.out.println("The base entered was: " + baseDimension); System.out.println("The height entered was: " + heightDimension); // Create the Triangle object Triangle myTriangle = new Triangle(); // Set values from user myTriangle.setBaseDimension(baseDimension); myTriangle.setHeightDimension(heightDimension); // Calculate the area myTriangle.computeArea(); area = myTriangle.getArea(); // Show the feedback dialog outBox.show(); // Return the calculated area outBox.println("The triangle area was computed to be: " + area); }
public static void main(String[] args) { Object[] objects = {new Triangle(5, 5), new Square(3), new Circle(3)}; // compute areas for (Object o : objects) { if (o instanceof Triangle) { System.out.println("The name of the class is : " + o.getClass().getSimpleName()); Triangle t = (Triangle) o; System.out.println("Area of Triangle : " + t.computeArea()); } if (o instanceof Square) { System.out.println("The name of the class is : " + o.getClass().getName()); Square s = (Square) o; System.out.println("Area of Rectangle : " + s.computeArea()); } if (o instanceof Circle) { Circle c = (Circle) o; System.out.println("The name of the class is : " + o.getClass()); System.out.println("Area of Circle : " + c.computeArea()); } } }