LocalDate msBaseDate = LocalDate.of(1899, Month.DECEMBER, 30);
int[] integers = { 4305, 4304, 4303 };
for (int integerValue : integers) {
LocalDate date = msBaseDate.plusDays(integerValue);
System.out.println(date);
}
Output from this snippet is:
1911-10-14
1911-10-13
1911-10-12
Excel and other Microsoft products and possibly other software too use December 30, 1899, as a base date and represent dates as a count of days since that date. So just add the number to that date. I am using LocalDate
from java.time, the modern Java date and time API.
Question: Can I use java.time on Android?
Yes, java.time works nicely on older and newer Android devices. It just requires at least Java 6.
- In Java 8 and later and on newer Android devices (from API level 26) the modern API comes built-in.
- In Java 6 and 7 get the ThreeTen Backport, the backport of the modern classes (ThreeTen for JSR 310; see the links at the bottom).
- On (older) Android use the Android edition of ThreeTen Backport. It’s called ThreeTenABP. And make sure you import the date and time classes from
org.threeten.bp
with subpackages.
Links