Calculate days between two Dates in Java 8

Question

I know there are lots of questions on SO about how to get Dates in Java, but I want an example using new Java 8 Date API. I also know about the JodaTime library, but I want a method without relying on external libraries.

The function needs to be compliant with these restrictions:

1. Prevent errors from date savetime
2. Inputs are two Date objects (without time, I know about LocalDateTime, but I need to do this with Date instances)

Answer 1

If you want logical calendar days, use DAYS.between() method from java.time.temporal.ChronoUnit:

LocalDate dateBefore; LocalDate dateAfter; long daysBetween = DAYS.between(dateBefore, dateAfter); 

If you want literal 24 hour days, (a duration), you can use the Duration class instead:

LocalDate today = LocalDate.now() LocalDate yesterday = today.minusDays(1); // Duration oneDay = Duration.between(today, yesterday); // throws an exception Duration.between(today.atStartOfDay(), yesterday.atStartOfDay()).toDays() // another option 

For more information, refer to this document.

Answer 2

Based on VGR's comments here is what you can use:

ChronoUnit.DAYS.between(firstDate, secondDate)