运用哈希表

import java.util.Scanner;
import java.util.HashMap;

public class Main{
    public static void main(String[] args){
        Scanner in = new Scanner(System.in);
        HashMap<String,String> hMap = new HashMap<>();
        hMap.put("reset","reset what");
        hMap.put("reset board","board fault");
        hMap.put("board add","where to add");
        hMap.put("board delete","no board at all");
        hMap.put("reboot backplane","impossible");
        hMap.put("backplane abort","install first");
        while(in.hasNext()){
            String ss = in.nextLine();
            if(hMap.containsKey(ss)){
                System.out.println(hMap.get(ss));
            }
            else{
                System.out.println("unknown command");
            }
        }
    }
}