Calculating elasped time between Midnight and current time

Question

I'm trying to determine how many hours, minutes, seconds have passed throughout the day.

The timer restarts at midnight for every new day.

So if the current time is 2:15 PM, I need to calculate that to be 14 hours and fifteen minutes.

I know how to do this in .Net easily, but unfortunately I'm not as familiar with Android and Java's Calendar/date classes.

It appears the Date class is somewhat deprecated at this point.

Can anyone point me in the right direction?

Thanks.

Answer 1

You can use the Calendar class to get this. You can get a Calendar set to midnight like this:

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

Then you can get the time in millis or use other methods to get hours/minutes/seconds, etc.

cal.getTimeInMillis(); 

Answer 2

You can do the following:

// 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);
}

}

Usage :

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