/// <summary> /// <inheritDoc/> /// /// </summary> public virtual Antlr4.Runtime.Misc.IntervalSet And(IIntSet other) { if (other == null) { //|| !(other instanceof IntervalSet) ) { return(null); } // nothing in common with null set IList <Interval> myIntervals = this.intervals; IList <Interval> theirIntervals = ((Antlr4.Runtime.Misc.IntervalSet)other).intervals; Antlr4.Runtime.Misc.IntervalSet intersection = null; int mySize = myIntervals.Count; int theirSize = theirIntervals.Count; int i = 0; int j = 0; // iterate down both interval lists looking for nondisjoint intervals while (i < mySize && j < theirSize) { Interval mine = myIntervals[i]; Interval theirs = theirIntervals[j]; //System.out.println("mine="+mine+" and theirs="+theirs); if (mine.StartsBeforeDisjoint(theirs)) { // move this iterator looking for interval that might overlap i++; } else { if (theirs.StartsBeforeDisjoint(mine)) { // move other iterator looking for interval that might overlap j++; } else { if (mine.ProperlyContains(theirs)) { // overlap, add intersection, get next theirs if (intersection == null) { intersection = new Antlr4.Runtime.Misc.IntervalSet(); } intersection.Add(mine.Intersection(theirs)); j++; } else { if (theirs.ProperlyContains(mine)) { // overlap, add intersection, get next mine if (intersection == null) { intersection = new Antlr4.Runtime.Misc.IntervalSet(); } intersection.Add(mine.Intersection(theirs)); i++; } else { if (!mine.Disjoint(theirs)) { // overlap, add intersection if (intersection == null) { intersection = new Antlr4.Runtime.Misc.IntervalSet(); } intersection.Add(mine.Intersection(theirs)); // Move the iterator of lower range [a..b], but not // the upper range as it may contain elements that will collide // with the next iterator. So, if mine=[0..115] and // theirs=[115..200], then intersection is 115 and move mine // but not theirs as theirs may collide with the next range // in thisIter. // move both iterators to next ranges if (mine.StartsAfterNonDisjoint(theirs)) { j++; } else { if (theirs.StartsAfterNonDisjoint(mine)) { i++; } } } } } } } } if (intersection == null) { return(new Antlr4.Runtime.Misc.IntervalSet()); } return(intersection); }