Java 8 - Convert LocalDate to ZonedDateTime

Question

I'm new to java.time package. I have a LocalDate 2015-12-10. I need to convert this to ZonedDateTime. Time should be 00:00:00 and Zone is ZoneOffset.UTC.

After conversion, ZonedDateTime should be 2015-12-10T00:00:00+02:00.

I'm storing the LocalDate in a variable called startDate.

I tried:

ZonedDateTime.ofInstant(Instant.from(startDate), ZoneOffset.UTC) 

but get the error

java.time.DateTimeException: Unable to obtain Instant from TemporalAccessor: 2015-12-10 of type java.time.LocalDate]

I also tried:

startDate.atStartOfDay().atZone(ZoneOffset.UTC) 

This gives unexpected results.

I looked at the API and tried a few other methods, but no luck so far.

Is there any other way to convert LocalDate to ZonedDateTime?

Answer 1

When converting less specific objects to more specific ones, use the 'at' methods:

ZonedDateTime zdt = startDate.atStartOfDay(ZoneOffset.UTC); 

Passing in the UTC offset will not get a result of +02:00 however, which suggests you are trying to achieve something else.

Answer 2

I supose the issue isn't relevant anymore but for google-purposes:

  LocalDate localDate = LocalDate.parse("2017-07-22");         ZonedDateTime zonedDateTime = localDate.atStartOfDay(ZoneId.systemDefault());   // => 2017-07-22T00:00+05:30[Asia/Kolkata] 

source https://beginnersbook.com/2017/10/java-convert-localdate-to-zoneddatetime/