I know some tricks are played with the time zone database, compared to regular Java environments, simply for performance issues. It used to be the first time you used something that touched time zones that your app would freeze for a full second while the database was loaded. Now, they pre-load the time zone database in zygote and share it among all VMs. It's possible that there's a bug introduced in that process.
I would file an issue on this at b.android.com, with a complete project containing your source code that demonstrates the error. On Tue, Jan 24, 2012 at 6:18 AM, Jan Skarvall <[email protected]> wrote: > Hi all > > I have discovered a problem with getting correct DST saving value, > . > TimeZone.getDSTSavings() normally returns 3600000 (1 hour), but should > for timezone ID "Australia/Lord_Howe" return 1800000 (30 minutes). > (See http://www.timeanddate.com/worldclock/clockchange.html?n=750) > > I believe that GregorianCalendar uses TimeZone.getDSTSavings(), but > that is only my guess from looking at the source at > http://www.java2s.com/Open-Source/Android/android-core/platform-libcore/java/util/GregorianCalendar.java.htm > > Now, if I instead of using TimeZone.getDSTSavings() looks att what > GregorianCalendar.get(Calendar.DST_OFFSET) returns, it is infact > 1800000 when DST is on, which the following App reveals: > > package x.getdstavingsissue; > /* > * Result on Android 2.2 is: > * TimeZone.getDSTSavings() == 3600000 > * GregorianCalendar DST_OFFSET == 1800000 > */ > import java.util.Calendar; > import java.util.TimeZone; > > import android.app.Activity; > import android.os.Bundle; > import android.util.Log; > import android.widget.TextView; > > public class GetDSTSavingsIssueActivity extends Activity { > /** Called when the activity is first created. */ > @Override > public void onCreate(Bundle savedInstanceState) { > super.onCreate(savedInstanceState); > setContentView(R.layout.main); > Calendar cal = > Calendar.getInstance(TimeZone.getTimeZone("Australia/Lord_Howe")); > int getdstsavings = cal.getTimeZone().getDSTSavings(); > cal.set(2012, 1, 1, 0, 0, 0); > cal.set(Calendar.MILLISECOND, 0); > int caldstsavings = cal.get(Calendar.DST_OFFSET); > ((TextView) findViewById(R.id.getdstsavings)) > .setText("TimeZone.getDSTSavings() == " + > String.valueOf(getdstsavings)); > ((TextView) findViewById(R.id.caldstsavings)) > .setText("GregorianCalendar DST_OFFSET == " + > String.valueOf(caldstsavings)); > Log.d("GetDSTSavingsIssue", "TimeZone.getDSTSavings() == " + > String.valueOf(getdstsavings)); > Log.d("GetDSTSavingsIssue", "GregorianCalendar DST_OFFSET == " > + > String.valueOf(caldstsavings)); > } > } > > I tried running on 2.2 in emulator and on a device, and also on 3.2 in > emulator. Same result. > > So, I wonder how this can be. > > Regards > Jan > > -- > You received this message because you are subscribed to the Google > Groups "Android Developers" group. > To post to this group, send email to [email protected] > To unsubscribe from this group, send email to > [email protected] > For more options, visit this group at > http://groups.google.com/group/android-developers?hl=en -- Mark Murphy (a Commons Guy) http://commonsware.com | http://github.com/commonsguy http://commonsware.com/blog | http://twitter.com/commonsguy Android Training in DC: http://marakana.com/training/android/ -- You received this message because you are subscribed to the Google Groups "Android Developers" group. To post to this group, send email to [email protected] To unsubscribe from this group, send email to [email protected] For more options, visit this group at http://groups.google.com/group/android-developers?hl=en
