* One way to implement this would be to create multiple instanceof-checks for the methods parameter. * However, this creates a maintenance issue. When new types are added we would also need to change * the method's implementation and add a new instanceof-check. This violates the single responsibility * principle - a class should have only one reason to change. - * + *
* Instead of the instanceof-checks a better way is to make another virtual call on the parameter * object. This way new functionality can be easily added without the need to modify existing * implementation (open-closed principle). - * - * In this example we have hierarchy of objects (GameObject) that can collide to each other. Each + *
+ * In this example we have hierarchy of objects ({@link GameObject}) that can collide to each other. Each
* object has its own coordinates which are checked against the other objects' coordinates. If
* there is an overlap, then the objects collide utilizing the Double Dispatch pattern.
*
*/
public class App {
+ /**
+ * Program entry point
+ * @param args command line args
+ */
public static void main( String[] args ) {
// initialize game objects and print their status
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