如何计算两个日期之间的正常实际月份数？ [英] How to calculate properly actual month count between 2 dates?

问题描述

用于计算两个日期和重新$ P $整数的回报率地图之间的差异

我按照方法 getDiffDateMap psent毫秒，秒，​​分钟，小时，天，分别几个月甚至几年。

 公共静态地图＆LT;整数，字符串＆GT; getDiffDateMap（字符串dateA，字符串dateB）{    日历CAL = Calendar.getInstance（）;
    地图＆LT;整数，字符串＆GT; OUT =新的LinkedHashMap＆LT;整数，字符串＆GT;（）;
    长timeInMillA = 0;
    长timeInMillB = 0;    SimpleDateFormat的日期格式=新的SimpleDateFormat（YYYY-MM-DD HH：MM：SS）;    日期convertedDateA;
    日期convertedDateB;    尝试{
        convertedDateA = dateFormat.parse（dateA）;
        cal.setTime（convertedDateA）;
        timeInMillA = cal.getTimeInMillis（）;
        convertedDateB = dateFormat.parse（dateB）;
        cal.setTime（convertedDateB）;
        timeInMillB = cal.getTimeInMillis（）;    }赶上（ParseException的E）{
        e.printStackTrace（）;
    }    长毫= timeInMillB  -  timeInMillA;
    长秒=毫/ 1000;
    龙敏=秒/ 60;
    长小时=分钟/ 60;
    漫长的一天=小时/ 24;
    漫长的一周= / 7天;
    漫长的一个月= / 31天; // ????
    漫长的一年=月/ 12;    out.put（7，米利+）;
    out.put（6秒+）;
    out.put（5，分钟+）;
    out.put（4，小时+）;
    out.put（3，天+）;
    out.put（2，每周+）;
    out.put（1，月+）;
    out.put（0，+一年）;    返回的;
}
 

我的问题是，从实际的天数计算月：

 长月=日/ 31日; //或30
 

例如：

 地图＆LT;整数，字符串＆GT;出= getDiffInMillsec（2012年9月1日20：9：01，20时10分01秒2012-10-01）;    的System.out.println（Arrays.asList（出））;
 

我得到的输出： [{7 = 2592060000，6 = 2592060，5 = 43201，4 = 720，3 = 30，2 = 4,1 = 0,0 = 0}] ，其中 1 是月计数和0，因为不同的是只有30天。流量是什么我需要添加到解决这个问题？有什么建议？

解决方案

  

我按照一个计算两个日期之间的差值，并返回地图分别重新present毫秒，秒，​​分钟，小时，天，月，年的整数方法getDiffDateMap。

不要重新发明轮子：）

乔达时间有code ++做的这一切和更多。例如：

  LocalDateTime开始= ...;
LocalDateTime结束= ...;
期差=新周期（开始，结束，PeriodType.yearMonthDayTime（））;
INT个月= difference.getMonths（）; //等
 

请注意，您的不能的获得在几个月的数量当你刚刚转换的不同，以毫秒数 - 为月数将取决于开始/结束日期。 （30天可以是或可以不是一个月，例如...）

我强烈建议你使用乔达时间整个的Java code，在preference到的java.util。* 。这是一个的多的更好的API，和一个希望这将意味着你很少-IF-以往任何时候都需要编写自己的日期/时间处理code。

I have followed method getDiffDateMap that calculates difference between 2 dates and returns Map of Integers that represent milliseconds, seconds, minutes, hours, days, months and years respectively.

public static Map<Integer, String> getDiffDateMap(String dateA, String dateB) {

    Calendar cal = Calendar.getInstance();      
    Map<Integer,String> out = new LinkedHashMap<Integer, String>();
    long timeInMillA = 0;
    long timeInMillB = 0;

    SimpleDateFormat dateFormat = new SimpleDateFormat("yyyy-MM-dd HH:mm:ss"); 

    Date convertedDateA;
    Date convertedDateB;



    try {
        convertedDateA = dateFormat.parse(dateA);           
        cal.setTime(convertedDateA);
        timeInMillA = cal.getTimeInMillis();


        convertedDateB = dateFormat.parse(dateB);           
        cal.setTime(convertedDateB);
        timeInMillB = cal.getTimeInMillis();

    } catch (ParseException e) {
        e.printStackTrace();
    } 

    long mili = timeInMillB - timeInMillA;
    long sec = mili/1000;
    long min = sec/60;
    long hour = min/60;
    long day = hour/24;
    long week = day/7;
    long month = day/31; // ????
    long year = month/12;

    out.put(7, mili + "");
    out.put(6, sec + "");
    out.put(5, min + "");
    out.put(4, hour + "");
    out.put(3, day + "");
    out.put(2, week + "");
    out.put(1, month + "");
    out.put(0, year + "");

    return out;
}

My problem is to calculate month from actual day count:

long month = day/31; // or 30

For example:

Map<Integer,String> out = getDiffInMillsec("2012-9-01 20:9:01", "2012-10-01 20:10:01");

    System.out.println(Arrays.asList(out)); 

I get output: [{7=2592060000, 6=2592060, 5=43201, 4=720, 3=30, 2=4, 1=0, 0=0}] where 1 is month count and its 0. because difference is 30 days only. What flow need I add to fix this problem? Any suggestions?

解决方案

I have followed method getDiffDateMap that calculates difference between 2 dates and returns Map of Integers that represent milliseconds, seconds, minutes, hours, days, months and years respectively.

Don't reinvent the wheel :)

Joda Time has code to do all this and more. For example:

LocalDateTime start = ...;
LocalDateTime end = ...;
Period difference = new Period(start, end, PeriodType.yearMonthDayTime());
int months = difference.getMonths(); // etc

Note that you can't get at the number of months when you've just converted the different to a number of milliseconds - as the number of months will depend on the start/end date. (30 days may or may not be a month, for example...)

I'd strongly advise you to use Joda Time throughout your Java code, in preference to java.util.*. It's a much better API, and one which will hopefully mean you rarely-if-ever need to write your own date/time handling code.

这篇关于如何计算两个日期之间的正常实际月份数？的文章就介绍到这了，希望我们推荐的答案对大家有所帮助，也希望大家多多支持IT屋！