Question

我有一个Event类，它使用PriorityQueue和我自己定义的Time类用于Event类。

static class Event implements Comparable<Event>{
    Customer customer;
    Time eventTime;
    char eventType;

    public int compareTo(Event e){
        int n = e.eventTime.compareTo(eventTime);
        int compare = 0;

        if(n < 0){
            compare = -1;
        }
        else if(n == 0){
            compare = 0;
        }
        else if(n > 0){
            compare = 1;
        }
        return compare; 
    }
}


class Time{
    private int hour;
    private int minute;
    private boolean isMorning;

    public Time(){
        hour = 0;
        minute = 0;
        isMorning = true;
    }

    public Time(int h, int m, boolean morning){
        hour = h;
        minute = m;
        isMorning = morning;
    }

    public void setTime(int h, int m, boolean morning){
        hour = h;
        minute = m;
        isMorning = morning;
    }

    public int getHour(){
        return hour;
    }

    public int getMinute(){
        return minute;
    }

    public boolean isAM(){
        return isMorning;
    }

    public String toString(){
        String AM = "";
        String min = "";
        if(minute < 10){
            min = ("0" + minute);
        }
        else{
            min = ("" + minute);
        }
        if(isMorning){
            AM = "AM";
        }
        else{
            AM = "PM";
        }
        return ("" + hour + ":" + min + " " + AM);
    }


    public Time plus(int n){
        Time newTime = new Time();
        boolean newMorning = false;
        int minutes = minute + n;
        int newHour = minutes/60;
        int newMinutes = minutes%60;
        hour = hour + newHour;
        if(hour > 12){
            hour = hour - 12;
            if(isMorning){
                newMorning = false;
            }
            else{
                newMorning = true;
            }
        }
        newTime.setTime(hour, newMinutes, newMorning);
        return newTime;

    }

    public int timeDifference(Time t){

        int n = totalMinutes();
        int m = t.totalMinutes();

        return m - n;

    }

    public int compareTo(Time t){
        int n = totalMinutes();
        int m = t.totalMinutes();
        int compare = 0;

        if(n < m){
            compare = -1;
        }
        else if(n == m){
            compare = 0;
        }
        else if(n > m){
            compare = 1;
        }
        return compare;
    }

    private int totalMinutes(){
        int tempMinute = 0;
        if(!isMorning){
            if(hour == 12){

            }
            else{
            hour = hour + 12;
            tempMinute = (hour*60) + minute;
            }
        }
        else{
            if(hour == 12){
                tempMinute = minute;
            }
            else{
                tempMinute = (hour*60) + minute;
            }
        }
        return tempMinute;
    }

}

这不是我的所有代码，因为我有其他人只是持有稍后将插入到事件队列中的值。当我检查事件队列之外的时间时它与它应该的时间相匹配，比如我有一个Time对象为11:22 AM，但当我将它插入事件队列时，我的时间变为23:22 AM。由于某种原因，它在事件队列中增加了12个小时，我不明白为什么。

计算出totalMinutes（）方法正在弄乱小时，因为在隐式使用compareTo（）或timeDifference（）时会调用它。谢谢你的帮助！

Answer 1

首先，totalMinutes()与hour字段混淆时不应该。它应该使用局部变量。

其次，您的整个Event.compareTo(Event e)方法可以简化为

return e.eventTime.compareTo(eventTime);

这是回到前面，除非你想要最近的时间。尝试

return eventTime.compareTo(e.eventTime);

Java PriorityQueue无法正常工作？

1 个答案: