计算午夜和当前时间之间经过的时间

Question

我正在尝试确定一天中过去了多少小时、分钟、秒。

计时器在每个新的一天的午夜重新启动。

因此，如果当前时间是下午 2:15，我需要计算为 14 小时 15 分钟。

我知道如何在 .Net 中轻松做到这一点，但不幸的是，我对 Android 和 Java 的日历/日期类不太熟悉。

目前看来 Date 类有些过时了。

谁能指出我正确的方向？

谢谢。

Answer 1

您可以使用Calendar 类来获取此信息。您可以像这样将Calendar 设置为午夜：

Calendar cal = Calendar.getInstance();
cal.set(Calendar.HOUR_OF_DAY, 0);
cal.set(Calendar.MINUTE, 0);
cal.set(Calendar.SECOND, 0);

然后你可以得到毫秒的时间或者使用其他方法得到小时/分钟/秒等。

cal.getTimeInMillis(); 

Answer 2

您可以执行以下操作：

// get a calendar instance for midnight time
Calendar midnightCalendar = Calendar.getInstance();
midnightCalendar.set(Calendar.HOUR_OF_DAY, 0);
midnightCalendar.set(Calendar.MINUTE, 0);
midnightCalendar.set(Calendar.SECOND, 0);

long midnightTimeInMillis = midnightCalendar.getTimeInMillis();

// get a calendar instance for current time
Calendar currentTimeCalendar = Calendar.getInstance();

long currentTimeInMillis = currentTimeCalendar.getTimeInMillis();


// get the difference
long diffInMillis = currentTimeInMillis - midnightTimeInMillis;

// get the hours
int hours = (int)(diffInMillis / 3600 * 1000);

// get the minutes
int minutes = (int)(diffInMillis % 3600000) / (60 * 1000);

Answer 3

package com.umeng.comm.utils;

import android.annotation.SuppressLint;
import android.text.TextUtils;

import java.text.ParseException;
import java.text.SimpleDateFormat;
import java.util.Calendar;
import java.util.Date;

/**
 * 
 * @author mrsimple
 */
public class TimeUtils {

public static final long ONE_SECOND = 1000L;
public static final long ONE_MINUTE = 60000L;
public static final long ONE_HOUR = 3600000L;
public static final long ONE_DAY = 86400000L;
// private static final long ONE_WEEK = 604800000L;

/**
 * 
 */
public static final int ONE_YEAR_DAYS = 365;
/**
 * 
 */
public static final String JUST_NOW = "just now";

/**
 * 
 */
public static final String MINUTE_AGO = "munites ago";
/**
 * 
 */
public static final String HOUR_AGO = "hours ago ";

// private static final String TODAY = "Today ";

public static final String YESTERDAY = "Yestoday ";

public static final String THE_DAY_BEFORE_YESTERDAY = "the day before_yestoday ";
/**
 * 
 */
public static final String YEAR_AGO = "years ago";
/**
 * 
 */
@SuppressLint("SimpleDateFormat")
private static SimpleDateFormat mFormat = new SimpleDateFormat("yyyy-MM-dd HH:mm:ss");

/**
 * 
 * @param timeStr
 * @return
 */
public static String format(String timeStr) {
    if (!TextUtils.isEmpty(timeStr)) {
        try {
            Date date = mFormat.parse(timeStr);
            return format(date);
        } catch (Exception e) {
            e.printStackTrace();
        }
    }
    return timeStr;
}

/**
 * 
 * @param timeStr 
 * @return 
 */
public static long getTime(String timeStr){
    if ( TextUtils.isEmpty(timeStr) ) {
       return 0; 
    }
    try {
        return mFormat.parse(timeStr).getTime();
    } catch (ParseException e) {
        e.printStackTrace();
    }
    return 0;
}

/**
 * 
 * @param date
 * @return
 */
public static String format(Date date) {

    int days = getDayWithToday(date);
    long timeGap = getTimeGap(date);

    if (days == 0) {
        // return TODAY + getSimpleTimeStr(date);
        return getTodaysDateString(timeGap);
    }

    if (days == 1) {
        return YESTERDAY + getSimpleTimeStr(date);
    }

    if (days == 2) {
        return THE_DAY_BEFORE_YESTERDAY + getSimpleTimeStr(date);
    }

    return getSimpleDateStr(date);
}

private static long getTimeGap(Date date) {
    final long now = System.currentTimeMillis();
    return now - date.getTime();
}

private static String getTodaysDateString(long timegap) {
    if (timegap < ONE_MINUTE) {
        return JUST_NOW;
    } else if (timegap <= ONE_HOUR) {
        return timegap / ONE_MINUTE + MINUTE_AGO;
    }
    return timegap / ONE_HOUR + HOUR_AGO;
}

/**
 * @param date
 * @return
 */
private static int getDayWithToday(Date date) {
    // today's calendar
    Calendar calendar = Calendar.getInstance();
    int today = calendar.get(Calendar.DAY_OF_YEAR);
    int year = calendar.get(Calendar.YEAR);
    calendar.setTime(date);
    int createYear = calendar.get(Calendar.YEAR);

    int feedCreateDay = calendar.get(Calendar.DAY_OF_YEAR);

    return (today - feedCreateDay) + (year - createYear) * ONE_YEAR_DAYS;
}

/**
 * @return
 */
private static String getSimpleTimeStr(Date date) {
    SimpleDateFormat sdf = (SimpleDateFormat) SimpleDateFormat.getInstance();
    sdf.applyPattern("HH:mm");
    return sdf.format(date);
}

/**
 * @param date
 * @return
 */
private static String getSimpleDateStr(Date date) {
    SimpleDateFormat sdf = (SimpleDateFormat) SimpleDateFormat.getInstance();
    int days = getDayWithToday(date);
    String prefix = "";
    if (days >= ONE_YEAR_DAYS) {
        sdf.applyPattern("MM-dd");
        prefix = days / ONE_YEAR_DAYS + YEAR_AGO;
    } else {
        sdf.applyPattern("MM-dd HH:mm");
    }

    return prefix + sdf.format(date);
}

}

用法：

TimeUtils.format("2014-12-19 10:24:01");