While working on Java projects, we often need to increment or decrement date e.g. adding one day to the current date to get tomorrow's date, subtracting one day to get yesterday's date, etc. Since date in Java is maintained as long millisecond value, Sometimes, programmers tend to add 24 hours as one day, which could be wrong if day falls on a daylight saving time zone, where a day could be either 23 or 25 hour long. When you add or subtract days from date, other components' of date e.g. month and year must roll. In this Java date tutorial, we will see two ways to increment and decrement date in Java.