public int getMaxElement() {
		if ( isNil() ) {
			throw new RuntimeException("set is empty");
		}
		Interval last = intervals.get(intervals.size()-1);
		return last.b;
	}
Returns the maximum value contained in the set if not isNil().

@return the maximum value contained in the set.
@throws RuntimeException if set is empty
runtime/Java/src/org/antlr/v4/runtime/misc/IntervalSet.java