How to find difference between two Joda-Time DateTimes in minutes

Distinguishing Duration and Periods

It's vital to understand Duration and Period conceptually. Duration indicates a specified length of time in milliseconds, while Period represents a field-based timespan such as years, months, days etc.

For precision-based calculations with Duration, you'd do this:

Duration duration = new Duration(startDateTime, endDateTime);
long durationInMinutes = duration.getStandardMinutes(); // Go, go gadget Duration!
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Now, if you have periods which span daylight saving changes or involves months and years, use Period:

Period period = new Period(startDateTime, endDateTime, PeriodType.minutes());
int periodInMinutes = period.getMinutes(); // Yay! I'm well tracked in Periodic Table.. Umm.. I mean Periods!
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Managing across days boundaries

When differences involve day boundaries, or when your program has a curfew, adjustments using minusDays() help:

DateTime previousDate = endDateTime.minusDays(1);  // Time travelling like Marty McFly!
int diffInMinutesAcrossDays = Minutes.minutesBetween(previousDate, endDateTime).getMinutes();
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Fine-tuning computations

For moments when precision is a must, subtract the getMillis() values and convert the difference to minutes:

long startMillis = startDateTime.getMillis();
long endMillis = endDateTime.getMillis();
int diffInMinutesPrecise = (int)((endMillis - startMillis) / 60000); // Fine-tuning, like a watchmaker!
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Beware, Joda-Time doesn't consider leap seconds, but this should work unless you're timing a rocket launch.

Closet full of computational errors

Remember to initialize DateTime objects accurately:

DateTimeFormatter formatter = DateTimeFormat.forPattern("yyyy-MM-dd HH:mm:ss");
DateTime startDateTime = formatter.parseDateTime("2023-01-01 14:00:00");  // Ready, set, datetime!
DateTime endDateTime = formatter.parseDateTime("2023-01-01 14:45:00");  // And...we're datetime!
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Poor initialization can cause discrepancies that put Gandalf to shame (you shall not parse!).

Mind the timezone

Like clothes, timezones can drastically change how your DateTime objects fit. If your objects exists in different time zones or spans daylight saving transitions, use Joda-Time's solid timezone handling. A stitch in time saves nine, right?

DateTimeZone zone = DateTimeZone.forID("America/New_York");
DateTime startDateTimeWithZone = startDateTime.withZone(zone); // New York, New York!
DateTime endDateTimeWithZone = endDateTime.withZone(zone); // I'm already missing the Big Apple...
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