Java进阶学习（5）之设计原则(下)

框架加数据

• 把数据的硬编码尽可能解成框架加数据的结构
• 城堡游戏修改后的代码
  • 　　Room类

  •  1 package com.castle;
     2 
     3 import java.util.HashMap;
     4 
     5 public class Room {
     6     private String description;
     7     private HashMap exits=new HashMap();
     8     
     9 
    10     public Room(String description) 
    11     {
    12         this.description = description;
    13     }
    14 
    15     public String getEixtDesc()
    16     {
    17         StringBuffer sb=new StringBuffer();
    18         for (String dir : exits.keySet())
    19         {
    20             sb.append(dir+" ");
    21         }
    22         return sb.toString();
    23     }
    24     
    25     public void setExit(String dir,Room room)
    26     {
    27         exits.put(dir, room);
    28     }
    29     
    30 
    31     public Room getExit(String direction)
    32     {
    33         return exits.get(direction);
    34     }
    35     
    36     @Override
    37     public String toString()
    38     {
    39         return description;
    40     }
    41 }

     

  • Game类

  •   1 package com.castle;
      2 
      3 import java.util.HashMap;
      4 import java.util.Scanner;
      5 
      6 public class Game {
      7     private Room currentRoom;
      8         
      9     private HashMap handlers=new HashMap();
     10     public Game() 
     11     {
     12         handlers.put("go", new HandlerGo(this));
     13         handlers.put("Bye", new HandlerBye(this));
     14         handlers.put("Help", new HandlerHelp(this));
     15         createRooms();
     16     }
     17 
     18     private void createRooms()
     19     {
     20         Room outside, lobby, pub, study, bedroom;
     21       
     22         //    制造房间
     23         outside = new Room("城堡外");
     24         lobby = new Room("大堂");
     25         pub = new Room("小酒吧");
     26         study = new Room("书房");
     27         bedroom = new Room("卧室");
     28         
     29         //    初始化房间的出口
     30         outside.setExit("east", lobby) ;
     31         outside.setExit("south", study) ;
     32         outside.setExit("west", pub) ;
     33         
     34         lobby.setExit("west", outside) ;
     35         
     36         pub.setExit("east", outside) ;
     37         
     38         study.setExit("north", outside) ;
     39         study.setExit("east", bedroom) ;
     40         
     41         bedroom.setExit("west", study) ;
     42         
     43         lobby.setExit("up", pub);
     44         pub.setExit("down", lobby);
     45         
     46        
     47 
     48         currentRoom = outside;  //    从城堡门外开始
     49     }
     50 
     51     private void printWelcome() {
     52         System.out.println();
     53         System.out.println("欢迎来到城堡！");
     54         System.out.println("这是一个超级无聊的游戏。");
     55         System.out.println("如果需要帮助，请输入 'help' 。");
     56         System.out.println();
     57         showPrompt();
     58         
     59     }
     60 
     61     // 以下为用户命令
     62 
     63   
     64 
     65     public void showPrompt()
     66     {
     67         System.out.println("你在" + currentRoom);
     68         System.out.print("出口有: ");
     69         System.out.println(currentRoom.getEixtDesc());
     70         System.out.println();
     71     }
     72     
     73     public void goRoom(String direction) 
     74     {
     75         Room nextRoom = currentRoom.getExit(direction);
     76         
     77         if (nextRoom == null) {
     78             System.out.println("那里没有门！");
     79         }
     80         else {
     81             currentRoom = nextRoom;
     82             showPrompt();
     83         }
     84     }
     85     
     86     public void play()
     87     {
     88         Scanner in = new Scanner(System.in);
     89         while ( true ) {
     90             String line = in.nextLine();
     91             String[] words = line.split(" ");
     92             Handler handler=handlers.get(words[0]);
     93             String value="";
     94             if(words.length>1)
     95                 value=words[1];
     96             if(handler !=null) 
     97             {
     98                 handler.doCmd(value);
     99                 if(handler.isBye())
    100                     break;
    101             }
    102 //            if ( words[0].equals("help") ) {
    103 //                printHelp();
    104 //            } else if (words[0].equals("go") ) {
    105 //                goRoom(words[1]);
    106 //            } else if ( words[0].equals("bye") ) {
    107 //                break;
    108 //            }
    109         }
    110         in.close();
    111     }
    112     
    113     public static void main(String[] args) {
    114         Game game = new Game();
    115         game.printWelcome();
    116         game.play();
    117         System.out.println("感谢您的光临。再见！");
    118     }
    119 
    120 }

     

  • Handler类及其子类

  •  1 package com.castle;
     2 
     3 public class Handler
     4 {
     5 
     6     protected Game game;
     7     
     8     
     9     
    10     public Handler(Game game)
    11     {
    12         
    13         this.game = game;
    14     }
    15     public void doCmd(String word) {}
    16     public boolean isBye() {return false;}
    17     public static void main(String[] args)
    18     {
    19         // TODO Auto-generated method stub
    20 
    21     }
    22 
    23 }
    24 
    25 
    26 
    27 package com.castle;
    28 
    29 public class HandlerBye extends Handler
    30 {
    31 
    32     public HandlerBye(Game game)
    33     {
    34         super(game);
    35         // TODO Auto-generated constructor stub
    36     }
    37 
    38     @Override
    39     public boolean isBye()
    40     {
    41         // TODO Auto-generated method stub
    42         return true;
    43     }
    44 
    45 }
    46 
    47 
    48 
    49 
    50 package com.castle;
    51 
    52 public class HandlerHelp extends Handler
    53 {
    54 
    55     public HandlerHelp(Game game)
    56     {
    57         super(game);
    58         // TODO Auto-generated constructor stub
    59     }
    60 
    61     @Override
    62     public void doCmd(String word)
    63     {
    64         System.out.print("迷路了吗？你可以做的命令有：go bye help");
    65         System.out.println("如：\tgo east");
    66     }
    67 
    68 }
    69 
    70 
    71 
    72 
    73 package com.castle;
    74 
    75 public class HandlerGo extends Handler
    76 {
    77 
    78     public HandlerGo(Game game)
    79     {
    80         super(game);
    81         // TODO Auto-generated constructor stub
    82     }
    83 
    84     @Override
    85     public void doCmd(String word)
    86     {
    87         // TODO Auto-generated method stub
    88         game.goRoom(word);
    89     }
    90 
    91 }