/** * An abstract class that is common to several games in * which players play against the others, but only one is * playing at a given time. */ abstract class Game { private int playersCount; abstract void initializeGame(); abstract void makePlay(int player); abstract boolean endOfGame(); abstract void printWinner(); /* A template method : */ final void playOneGame(int playersCount) { this.playersCount = playersCount; initializeGame(); int j = 0; while (!endOfGame()){ makePlay(j); j = (j + 1) % playersCount; } printWinner(); } } //Now we can extend this class in order to implement actual games: class Monopoly extends Game { /* Implementation of necessary concrete methods */ void initializeGame() { // ... } void makePlay(int player) { // ... } boolean endOfGame() { // ... } void printWinner() { // ... } /* Specific declarations for the Monopoly game. */ // ... } class Chess extends Game { /* Implementation of necessary concrete methods */ void initializeGame() { // ... } void makePlay(int player) { // ... } boolean endOfGame() { // ... } void printWinner() { // ... } /* Specific declarations for the chess game. */ // ... }