}
protected long computeMilliseconds(MatchedEventMap beginState, PatternAgentInstanceContext context) {
if (millisecondsExpr instanceof ExprTimePeriod) {
ExprTimePeriod timePeriod = (ExprTimePeriod) millisecondsExpr;
return timePeriod.nonconstEvaluator().deltaMillisecondsUseEngineTime(convertor.convert(beginState), context.getAgentInstanceContext());
}
else {
Object millisecondVal = PatternExpressionUtil.evaluate("Timer-Within-Or-Max-Count guard", beginState, millisecondsExpr, convertor, context.getAgentInstanceContext());
if (null == millisecondVal) {
throw new EPException("Timer-within-or-max first parameter evaluated to a null-value");