Analog of ORACLE function MONTHS

Java是否具有Oracle的函数MONTHS_BETWEEN某些类比？

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You can do that with :

public static int monthsBetween(Date minuend, Date subtrahend){  

    Calendar cal = Calendar.getInstance();   
    cal.setTime(minuend);  
    int minuendMonth =  cal.get(Calendar.MONTH);  
    int minuendYear = cal.get(Calendar.YEAR);  
    cal.setTime(subtrahend);  
    int subtrahendMonth =  cal.get(Calendar.MONTH);  
    int subtrahendYear = cal.get(Calendar.YEAR);  

    return ((minuendYear - subtrahendYear) * (cal.getMaximum(Calendar.MONTH)+1)) +    
    (minuendMonth - subtrahendMonth);  
}  

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Edit :

According to this documentation MONTHS_BETWEEN return a fractional result, I think this method do the same :

public static void main(String[] args) throws ParseException {
    SimpleDateFormat sdf = new SimpleDateFormat("dd/MM/yyyy");
    Date d = sdf.parse("02/02/1995");
    Date d2 = sdf.parse("01/01/1995");
    System.out.println(monthsBetween(d, d2));

}

public static double monthsBetween(Date baseDate, Date dateToSubstract){  

    Calendar cal = Calendar.getInstance();   
    cal.setTime(baseDate);
    int baseDayOfYear = cal.get(Calendar.DAY_OF_YEAR);  
    int baseMonth =  cal.get(Calendar.MONTH);  
    int baseYear = cal.get(Calendar.YEAR);  

    cal.setTime(dateToSubstract);  
    int subDayOfYear = cal.get(Calendar.DAY_OF_YEAR);
    int subMonth =  cal.get(Calendar.MONTH);  
    int subYear = cal.get(Calendar.YEAR);  

    //int fullMonth = ((baseYear - subYear) * (cal.getMaximum(Calendar.MONTH)+1)) +    
    //(baseMonth - subMonth);  
    //System.out.println(fullMonth);

    return ((baseYear - subYear) * (cal.getMaximum(Calendar.MONTH)+1)) +   
           (baseDayOfYear-subDayOfYear)/31.0;
} 

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I've run into the same need and started from @alain.janinm answer which is good but doesn't give the exact same result in some cases.
ex :

Consider months between 17/02/2013 and 11/03/2016 ( "dd/MM/yyyy" )
Oracle result : 36,8064516129032
Java method from @Alain.janinm answer : 36.74193548387097

Here's the changes i made, to get a closer result to Oracle's months_between() function :

public static double monthsBetween(Date startDate, Date endDate){  

    Calendar cal = Calendar.getInstance(); 

    cal.setTime(startDate);  
    int startDayOfMonth = cal.get(Calendar.DAY_OF_MONTH);
    int startMonth =  cal.get(Calendar.MONTH);
    int startYear = cal.get(Calendar.YEAR);  

    cal.setTime(endDate);
    int endDayOfMonth = cal.get(Calendar.DAY_OF_MONTH);  
    int endMonth =  cal.get(Calendar.MONTH);
    int endYear = cal.get(Calendar.YEAR);  


    int diffMonths = endMonth - startMonth;
    int diffYears = endYear - startYear;
    int diffDays = endDayOfMonth - startDayOfMonth;

    return (diffYears * 12) + diffMonths + diffDays/31.0;
} 

With this function the result of the call for the dates 17/02/2013 and 11/03/2016 is : 36.806451612903224

Note : From my understanding Oracle's months_between() function considers that all months are 31 days long

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在Joda时间，org.joda.time.Months类中有几个月。

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