Question

我正在尝试制作一个迷你矩阵的东西。它应该做的就是射出一个0或1.这个代码很好，但我试图让它在开始时进行倒计时（3,2,1 - 然后开始）。它通过activate()在另一个文件中调用。

什么不起作用的是计时器。出于某种原因，它在前3个前面加上0：

03
2
1

它不会激活矩阵功能。这是代码，如果有人可以帮助我。

import java.util.Timer;
import java.util.TimerTask;

public class Matrix {

    public boolean matrix = true;
    static int interval;
    static Timer timer;

    public String activate() {
        String done = "";
        timer();
        return done;
    }

    private void matrix() {
        while(matrix) {
            System.out.print((int) (Math.random()+0.5));
            pressEnterToContinue();
        }
    }

    private void timer() {
        System.out.println("press ENTER to stop\n"+
                           "starting in");

        int delay = 1000;
        int period = 1000;

        timer = new Timer();
        interval = 3;
        timer.scheduleAtFixedRate(new TimerTask() {
            public void run() {
                System.out.println(setInterval());
            }
        }, delay, period);
        matrix();
    }

    private static final int setInterval() {
        if (interval == 1) {
            timer.cancel();
        }
        return interval--;
    }

     private void pressEnterToContinue() {
        try
        {
            System.in.read();
            matrix = false;
        }  
        catch(Exception e) {}  
    }
}

只是一个FYI，pressToContinue（）应该通过按ENTER结束while循环。

Answer 1

它是由

打印出来的

System.out.print((int) (Math.random()+0.5));

Answer 2

使用ScheduledExecutorService尝试此替代方案。

import java.util.Timer;
import java.util.concurrent.Executors;
import java.util.concurrent.ScheduledExecutorService;
import java.util.concurrent.ScheduledFuture;
import java.util.concurrent.TimeUnit;

public class Matrix {

 public boolean matrix = true;
 static int interval = 3;
 static Timer timer;
 private final ScheduledExecutorService scheduler =
       Executors.newScheduledThreadPool(1);

 public String activate() {
    String done = "";
    scheduleTimer();
    return done;
 }

 private void matrix() {
    while(matrix) {
        System.out.print((int) (Math.random()+0.5));
        pressEnterToContinue();
    }
 }

 public void scheduleTimer() {
    System.out.println("Starting in:");
    final Runnable timer = new Runnable() {
        public void run() { System.out.println(setInterval()); }
    };

    scheduler.scheduleAtFixedRate(timer, 1, 1, TimeUnit.SECONDS);

    try {
        scheduler.awaitTermination(1, TimeUnit.DAYS);
        matrix();
    } catch (InterruptedException e) {
        e.printStackTrace();
    }
 }

 private final int setInterval() {
    if (interval == 1) {
        scheduler.shutdown();
    }
    return interval--;
  }

  private void pressEnterToContinue() {
    try
    {
        System.in.read();
        matrix = false;
    }  
    catch(Exception e) {}  
 }

  public static void main(String[] args){
     Matrix mat = new Matrix();
     mat.activate();
  }
}

定时器功能问题

2 个答案: