lab8 finished

lab/lab8/Question8/Dot.java

@@ -0,0 +1,72 @@
+/*
+ * Author: CHEN Yongyuan (Walter) 1930006025 from OOP(1007)
+ * Date: 2022-04-14
+ * Description: This is the Dot class inherited from Shape class.
+ */
+
+public class Dot extends Shape {
+	/**
+	 * Constructor.
+	 *
+	 * @param x the x coordinate of the dot
+	 * @param y the y coordinate of the dot
+	 */
+	public Dot(double x, double y) {
+		super(x, y);
+	}
+
+	/**
+	 * Calculates the dot's area.
+	 *
+	 * @return the area of the dot
+	 */
+	public double area() {
+		return 0;
+	}
+
+	/**
+	 * Resize method of Dot throw an CannotResizeException with message "Cannot
+	 * resize a dot!"
+	 *
+	 * @param newSize the new size of the dot
+	 * @throws CannotResizeException the exception
+	 */
+	@Override
+	public void resize(double newSize) throws CannotResizeException {
+		throw new CannotResizeException("Cannot resize a dot!");
+	}
+
+	/**
+	 * Test.
+	 */
+	public static void testDot() {
+		Dot d = new Dot(1.2, 3.4);
+		// getX, getY, and move are inherited from Shape.
+		// area and resize come from Dot itself.
+		System.out.println(d.getX() == 1.2);
+		System.out.println(d.getY() == 3.4);
+		System.out.println(d.area() == 0.0);
+		// Move the dot. The area does not change.
+		d.move(7.8, 9.0);
+		System.out.println(d.getX() == 9.0);
+		System.out.println(d.getY() == 12.4);
+		System.out.println(d.area() == 0.0);
+		// Resize the dot. An exception is thrown, caught, and tested.
+		try {
+			d.resize(12.3);
+		} catch (Exception ex) {
+			System.out.println(ex.getMessage() == "Cannot resize a dot!");
+		}
+		// The area and position do not change.
+		System.out.println(d.getX() == 9.0);
+		System.out.println(d.getY() == 12.4);
+		System.out.println(d.area() == 0.0);
+
+		try {
+			d.resize(12.3);
+		} catch (CannotResizeException ex) {
+			System.out.println(ex.getMessage() == "Cannot resize a dot!");
+		}
+
+	}
+}