Question

I want to convert a Joda Time UTC DateTime object to local time.

Here’s a laborious way to do it which seems to work. But there must be a better way.

Here’s the code (in Scala) without surrounding declarations:

    val dtUTC = new DateTime("2010-10-28T04:00")
    println("dtUTC = " + dtUTC)
    val dtLocal = timestampLocal(dtUTC)
    println("local = " + dtLocal)

 def timestampLocal(dtUTC: DateTime): String = {
    // This is a laborious way to convert from UTC to local. There must be a better way.
    val instantUTC = dtUTC.getMillis
    val localDateTimeZone = DateTimeZone.getDefault
    val instantLocal = localDateTimeZone.convertUTCToLocal(instantUTC)
    val dtLocal = new DateTime(instantLocal)
    dtLocal.toString
  }

Here’s the output:

dtUTC = 2010-10-28T04:00:00.000+11:00
local = 2010-10-28T15:00:00.000+11:00

Answer 1

Here’s what I use on a current project.

val marketCentreTime = timeInAnotherTimezone.withZone(DateTimeZone.forID("Australia/Melbourne"))

Does that help?

EDIT:

Here’s something that takes a time in the current TZ and converts to Brisbane time. You can use the same principle.

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scala> import org.joda.time._                                            
import org.joda.time._

scala> def timestampBrisbane(date: DateTime): String = {                      
     |   date.withZone(DateTimeZone.forID("Australia/Brisbane")).toString 
     | }
timestampBrisbane: (date: org.joda.time.DateTime)String

scala> val date = new DateTime
date: org.joda.time.DateTime = 2010-10-28T16:22:03.481+11:00

scala> val dateBrisbane = timestampBrisbane(date)
dateBrisbane: String = 2010-10-28T15:22:03.481+10:00