城堡游戏与消除代码复制
九十年代，那时候计算机有一种游戏城堡游戏
先创创建一个Game类
package demo02.clock.chengbao; import java.util.HashMap; import java.util.Scanner; public class Game { private Room currentRoom; private HashMap<String,Handler> handlers=new HashMap<String,Handler>(); public Game() { handlers.put("go", new HandlerGo(this)); handlers.put("bye", new HandlerBye(this)); handlers.put("help", new HandlerHelp(this)); createRooms(); } private void createRooms() { Room outside, lobby, pub, study, bedroom,bedroom1; // 制造房间 outside = new Room("城堡外"); lobby = new Room("大堂"); pub = new Room("小酒吧"); study = new Room("书房"); bedroom = new Room("卧室"); bedroom1 =new Room("次卧"); // 初始化房间的出口 outside.setExit("east",lobby); outside.setExit("south",study); outside.setExit("west",pub); lobby.setExit("west", outside); pub.setExit("east", outside); study.setExit("north",outside); study.setExit("east",bedroom); bedroom.setExit("west", study); bedroom.setExit("up", bedroom1); bedroom1.setExit("down", bedroom); currentRoom = outside; // 从城堡门外开始 } private void printWelcome() { System.out.println(); System.out.println("欢迎来到城堡！"); System.out.println("这是一个超级无聊的游戏。"); System.out.println("如果需要帮助，请输入 'help' 。"); System.out.println(); showPrompt(); } // 以下为用户命令 public void goRoom(String direction) { Room nextRoom = currentRoom.getExit(direction); if (nextRoom == null) { System.out.println("那里没有门！"); } else { currentRoom = nextRoom; showPrompt(); } } public void showPrompt() { System.out.println("现在你在" + currentRoom); System.out.print("出口有："); System.out.print(currentRoom.getExitDesc()); System.out.println(); } public void play() { Scanner in=new Scanner(System.in); while ( true ) { String line = in.nextLine(); String[] words = line.split(" "); Handler handler =handlers.get(words[0]); String value =""; if(words.length>1) value = words[1]; if(handler !=null) { handler.doCmd(value); if(handler.isBye()) { break; } } } } public static void main(String[] args) { Scanner in = new Scanner(System.in); Game game = new Game(); game.printWelcome(); game.play(); System.out.println("感谢您的光临。再见！"); in.close(); } }
Handler类
package demo02.clock.chengbao; import java.util.HashMap; import java.util.Scanner; public class Game { private Room currentRoom; private HashMap<String,Handler> handlers=new HashMap<String,Handler>(); public Game() { handlers.put("go", new HandlerGo(this)); handlers.put("bye", new HandlerBye(this)); handlers.put("help", new HandlerHelp(this)); createRooms(); } private void createRooms() { Room outside, lobby, pub, study, bedroom,bedroom1; // 制造房间 outside = new Room("城堡外"); lobby = new Room("大堂"); pub = new Room("小酒吧"); study = new Room("书房"); bedroom = new Room("卧室"); bedroom1 =new Room("次卧"); // 初始化房间的出口 outside.setExit("east",lobby); outside.setExit("south",study); outside.setExit("west",pub); lobby.setExit("west", outside); pub.setExit("east", outside); study.setExit("north",outside); study.setExit("east",bedroom); bedroom.setExit("west", study); bedroom.setExit("up", bedroom1); bedroom1.setExit("down", bedroom); currentRoom = outside; // 从城堡门外开始 } private void printWelcome() { System.out.println(); System.out.println("欢迎来到城堡！"); System.out.println("这是一个超级无聊的游戏。"); System.out.println("如果需要帮助，请输入 'help' 。"); System.out.println(); showPrompt(); } // 以下为用户命令 public void goRoom(String direction) { Room nextRoom = currentRoom.getExit(direction); if (nextRoom == null) { System.out.println("那里没有门！"); } else { currentRoom = nextRoom; showPrompt(); } } public void showPrompt() { System.out.println("现在你在" + currentRoom); System.out.print("出口有："); System.out.print(currentRoom.getExitDesc()); System.out.println(); } public void play() { Scanner in=new Scanner(System.in); while ( true ) { String line = in.nextLine(); String[] words = line.split(" "); Handler handler =handlers.get(words[0]); String value =""; if(words.length>1) value = words[1]; if(handler !=null) { handler.doCmd(value); if(handler.isBye()) { break; } } } } public static void main(String[] args) { Scanner in = new Scanner(System.in); Game game = new Game(); game.printWelcome(); game.play(); System.out.println("感谢您的光临。再见！"); in.close(); } }
HandlerBye类
package demo02.clock.chengbao; public class HandlerBye extends Handler { HandlerBye(Game game) { super(game); // TODO Auto-generated constructor stub } @Override public boolean isBye() { // TODO Auto-generated method stub return true; } @Override public void doCmd(String word) { // TODO Auto-generated method stub super.doCmd(word); } }
HandlerGo类
package demo02.clock.chengbao; public class HandlerGo extends Handler { HandlerGo(Game game) { super(game); // TODO Auto-generated constructor stub } @Override public void doCmd(String word) { // TODO Auto-generated method stub game.goRoom(word); } }
HandlerHelp类
package demo02.clock.chengbao; public class HandlerHelp extends Handler { HandlerHelp(Game game) { super(game); // TODO Auto-generated constructor stub } @Override public void doCmd(String word) { System.out.println("迷路了吗？你可以做的命令有：go bye help"); System.out.println("如：\tgo east"); } }
Room类
package demo02.clock.chengbao; import java.util.HashMap; public class Room { private String description; private HashMap<String,Room> exits=new HashMap<String,Room>(); public Room(String description) { this.description = description; } public void setExit(String dir,Room room) { exits.put(dir, room); } @Override public String toString() { return description; } public String getExitDesc() { StringBuffer ret=new StringBuffer(); for(String dir :exits.keySet()) { ret.append(dir); ret.append(" "); } return ret.toString(); } public Room getExit(String direction) { return exits.get(direction); } }
这个程序其实问题是非常多的，这程序暴露出来的问题，在面向对象程序设计当中的一些非常基本的原则，
原则第一条，就是 复制代码 代码复制是不良设计的一种表现
package demo02.clock.chengbao;
public class HandlerHelp extends Handler {
HandlerHelp(Game game) {
super(game);
// TODO Auto-generated constructor stub
}
@Override
public void doCmd(String word) {
System.out.println("迷路了吗？你可以做的命令有：go bye help");
System.out.println("如：\tgo east");
}
}
