2014-05-11 05:29
原题:
Design remote controller for me.
题目:设计一个遥控器。
解法:遥控什么?什么遥控?传统的红外线信号吗?我只能随便说说思路吧。不知道这算什么类型的面试题,真遇到的话也算是倒了霉了。想了半天恍然大悟:原来是考察设计模式。查了相关资料后发现命令模式比较符合题意,所以就依葫芦画瓢写了个例子。
代码:
1 // http://www.careercup.com/question?id=6366101810184192 2 interface ICommand { 3 public abstract void execute(); 4 } 5 6 public class PowerOnCommand implements ICommand { 7 @Override 8 public void execute() { 9 // TODO Auto-generated method stub 10 System.out.println("Power on."); 11 } 12 13 } 14 15 public class PowerOffCommand implements ICommand { 16 @Override 17 public void execute() { 18 // TODO Auto-generated method stub 19 System.out.println("Power off."); 20 } 21 } 22 23 import java.util.Vector; 24 25 public class RemoteController { 26 private Vector<ICommand> buttons; 27 private String[] configuration = {"PowerOnCommand", "PowerOffCommand"}; 28 29 public RemoteController() { 30 // TODO Auto-generated constructor stub 31 buttons = new Vector<ICommand>(); 32 for (String commandType : configuration) { 33 try { 34 try { 35 buttons.add((ICommand) Class.forName(commandType).newInstance()); 36 } catch (InstantiationException e) { 37 // TODO Auto-generated catch block 38 e.printStackTrace(); 39 } catch (IllegalAccessException e) { 40 // TODO Auto-generated catch block 41 e.printStackTrace(); 42 } 43 } catch (ClassNotFoundException e) { 44 // TODO Auto-generated catch block 45 e.printStackTrace(); 46 } 47 } 48 } 49 50 public void push(int commandIndex) { 51 try { 52 buttons.elementAt(commandIndex).execute(); 53 } catch (ArrayIndexOutOfBoundsException e) { 54 // TODO: handle exception 55 } 56 } 57 }