public String resolve(RequestContext context, RuleCriterion criterion) { String value = super.resolve(context, criterion); if (value != null) { return value; } Subject subject = context.getSubject(); if (subject == null) { String msg = "Invalid (null) Subject in request pipeline"; log.error(msg); return null; } return resolvePrincipals(context, criterion, subject, criterion.getName()); }