ATG Date Tag Converter is Buggy

Leaf on my car on Flickr

(Photo: Leaf on my car by exfordy)

The ATG Date Tag Converter is buggy because Java’s DateFormat is inherently unsafe for multithreaded use.  This is documented in ATG PR #123210 DateTagConverter.convertObjectToString() method is not thread safe.

You run into this problem whenever you do something like this.

Unfortunately there is no work around.  If using the Date Tag Converter is not causing problems for you, i.e you don’t see a stack trace like below, then you can ignore this bug.

2009-04-17 00:19:08,220 ERROR [nucleusNamespace.atg.dynamo.servlet.dafpipeline.DynamoServlet] java.lang.ArrayIndexOutOfBoundsException: 502
  at sun.util.calendar.BaseCalendar.getCalendarDateFromFixedDate(
  at java.util.GregorianCalendar.computeFields(
  at java.util.GregorianCalendar.computeFields(
  at java.util.Calendar.setTimeInMillis(
  at java.util.Calendar.setTime(
  at java.text.SimpleDateFormat.format(
  at java.text.SimpleDateFormat.format(
  at java.text.DateFormat.format(
  at atg.droplet.DateTagConverter.convertObjectToString(

But if you do see a bug like this then you might need to create a custom droplet to format the date.  The droplet should only use DateFormat instances that are not static.  I usually make my DateFormat instances local.

RQLQueryRange does not sort dates correctly

Roppongi District Desktop on Flickr

(Photo: Roppongi District Desktop by powerbooktrance)

This was bedeviling me for awhile.  I could not figure out why my RQLQueryRange droplet was not sorting by dates correctly.  It turns out this is a known ATG bug which only happens when you are using Oracle, which is 99% of the time.

Considering that this bug has been open since 2003 one can assume ATG is not interested in fixing it.  This is probably because there is a simple work around.

Instead of using the sortProperties parameter, put the the sort directive directly in the RQL statement in the queryRQL parameter.