I wonder for a while

Criteria crit = getSession().createCriteria(ApSummary.class)
.add(Restrictions.eq("controller.id", controllerId));

This "controller.id" surprises me a bit since when we do a join in Criteria query, generally we have to use createAlias() such as:

Criteria crit = getSession().createCriteria(ApSummary.class)
.createAlias("controller", "hwc").add(Restrictions.eq("hwc.id", controllerId));

The trick here is that controllre.id would be SMARTLY interpreted as column "controllerId" in ApSummary without doing the extra join!