How to get difference of months from Dates in Scala?-CodePudding

I have one date in format of date = "2022-07-03 10:09:19" Need to get difference of months from Today date and time

CodePudding user response：

You can leverage java.time library. Here is a sample code snippet:

import java.time.LocalDateTime
import java.time.temporal.ChronoUnit

val dateOld = "2022-07-03 10:09:19".replace(" ", "T")
val dateNew = "2022-11-03 10:09:19".replace(" ", "T")

val l1 = LocalDateTime.parse(dateOld)
val l2 = LocalDateTime.parse(dateNew)

val months = ChronoUnit.MONTHS.between(l1, l2)

For calculating from current time you can use:

val date = "2021-07-03 10:09:19".replace(" ", "T")

val l1 = LocalDateTime.parse(date)
val l3 = LocalDateTime.now()

val months = ChronoUnit.MONTHS.between(l1, l3)

Hope this helps !!

CodePudding user response：

Use ChronoUnit to solve it

import java.time.LocalDateTime
import java.time.temporal.ChronoUnit

DateTimeFormatter formatter = DateTimeFormatter.ofPattern("yyyy-MM-dd HH:mm:ss");
LocalDateTime previousDate = LocalDateTime.parse(date, formatter);
LocalDateTime now = LocalDateTime.now();

long diffMonths = ChronoUnit.MONTHS.between(now, previousDate);

CodePudding user response：

Use `java.time` if possible

You can parse the datetime String, add a time zone and take the current day or moment in the same time zone. Then you can extract the date and calculate the Period.between those two.

Here's an example in Java:

public static void main(String[] args) {
    // example input
    String someTime = "2022-07-03 10:09:19";
    // prepare a formatter that can parse such a String
    DateTimeFormatter dtf = DateTimeFormatter.ofPattern("uuuu-MM-dd HH:mm:ss");
    // prepare the time zone 
    // (I will use UTC, but the zone depends on the one of the input)
    ZoneId utc = ZoneId.of("UTC");
    // parse the String, apply the zone and directly extract the date
    LocalDate then = LocalDateTime.parse(someTime, dtf)
                                  .atZone(utc)
                                  .toLocalDate();
    // get the date of today in the zone
    LocalDate today = LocalDate.now(utc);
    // calculate the period between the two dates
    long months = ChronoUnit.MONTHS.between(then, today);
    // prepare some meaningful message to be printed
    String msg = String.format(
            "The difference in months between %s (then) and %s (today) is %d months",
            then, today, months);
    // and actually print it
    System.out.println(msg);
}

Output:

The difference in months between 2022-07-03 (then) and 2022-08-03 (today) is 1 months

CodePudding user response：

Parse the given date to an instance of java.time.LocalDateTime, then you can get an instance of java.time.Period for the two dates, and from that, you can get the months.

In Java:

final DateTimeFormatter parser = … // An appropriate parser for the given format
final var otherDate = LocalDateTime.parse( dateString, parser );
final var deltaPeriod = Period.between( LocalDateTime.now(), otherDate );
final var result = deltaPeriod.getYears() * 12   deltaPeriod.getMonths(); // or use Period::toTotalMonths()

Use java.time if possible

Use `java.time` if possible