java - 用户输入的时间限制

Question

我在为自己制作小游戏时遇到一些问题。我遇到问题的代码是用户输入超时。例如:游戏将在屏幕上显示一个字母。用户必须在特定时间之前输入该字母；如果他们不这样做，他们就会受到伤害。如果有人可以解释我可以用什么来解决这个问题，那就太好了。

package weapons;

import java.util.Random;
import java.util.Scanner;


class wepons {
    public static void main(String args[]){

        int weapondamage =0 , health = 0 , hits = 0, potion = 0, beast = 0, beastdmg = 0, letter = 0;
        String weapon;
        ;

        Scanner in = new Scanner (System.in);   

        System.out.println ("please pick a wepon that will kill the boss \n");
        weapon = in.nextLine().toLowerCase();
        if (weapon.equals("sword")){
          System.out.println("you have picked the sword");
          weapondamage = (int) ((Math.random()*100));
          health = weapondamage*3;
        }


        System.out.println("Sword damage is " + weapondamage);
        System.out.println("Boss health is " + health);
        System.out.println("Enter the amount of hits it will take to kill the boss.");
        hits = in.nextInt();
        if(hits == health/weapondamage) {
        System.out.println("you have killed the boss.The boss had droped a potion.\nYou pick up the potion and drink it!\nYour health has now gone up to 350hp");
        }

        else {

            System.out.print("You have failed to kill the boss");



        }
        potion = (int)350;
        beastdmg = (int) ((Math.random()*60));
        System.out.println("By killing the boss you have awoken the beast!");
        System.out.println("The beast nocks you onto your back");
        System.out.println("The beast will hit you for"+beastdmg+"damage");
        System.out.println("You can block the beast damage by hitting the write key");
        Random r = new Random();
        int c = r.nextInt(26) + (byte)'a';
        System.out.println((char)c);
        letter = in.next().charAt(0);
        if(  letter == ((char)c)){
            System.out.println("You blocked the beast damage");




        }
        else {

            System.out.print("You took damage");



        }
        }




        }  // main

Answer 1

有多种方法可以做到这一点，我正在以最简单的方式使用OP的风格来回答，因此测量用户按下字母的时间。这是一个功能片段:

    System.out.println("You can block the beast damage by hitting the write key");
    long startTime = System.currentTimeMillis();
    Random r = new Random();
    int c = r.nextInt(26) + (byte) 'a';
    System.out.println((char) c);
    char letter = in.next().charAt(0);
    long stopTime = System.currentTimeMillis();
    long elapsedTime = stopTime - startTime;
    if (letter == ((char) c) && elapsedTime <=5000) {
        System.out.println("You blocked the beast damage");

    } else {

        System.out.print("You took damage");

    }

希望有帮助。