org.jboss.as.ejb3.timerservice.CalendarTimer.Builder contains various fields for schedule attributes, such as seconds, minutes, hours, dayOfMonth, dayOfWeek, month, year, start, end, timezone, and their setter method. We should replace them with a single field of type ScheduleExpression to hold all these data.

Currently when user creating a calendar timer, a ScheduleExpression is passed in, which was then split into individual attributes to be set into the builder, and the builder sets all these to the new timer, which assembles them back into ScheduleExpression. This seems to be a waste.