/**
* Outputs filled with points listOfPointsToBeConnected. Finds the point with the lowest Y - that
* will be the first point of the broken line. If It finds several points with equal Ys - makes a
* line from the most left (lowest X) point to the most right point, then connects this point with
* next point with the lowest Y from the remaining set. The last point of the broken line will be
* the point with the highest Y, or if there will be several points with the highest Y - the point
* with the highest X from this set.
*/
void connectPoints() {
ArrayList<MyPoint> pointsInOneRow =
new ArrayList<MyPoint>(); // will store points with equal Ys.
MyPoint currentPoint, nextPoint;
ListIterator<MyPoint> itr;
while (randomListOfPoints.size() > 0) {
pointsInOneRow.clear(); // clear the pointsInOneRow.
itr = randomListOfPoints.listIterator();
// initialize list iterator and place it before the first element in the randomListOfPoints.
currentPoint = itr.next(); // the first element from the randomListOfPoints.
itr.remove(); // delete the first element from the randomListOfPoints.
if (itr.hasNext()) { // if it's not the end of the randomListOfPoints.
nextPoint = itr.next(); // the second element from the randomListOfPoints.
} else {
// the point not from the range of possible Xs and Ys, so we can be sure that its' Y won't
// be equal to the currentPoints'.
nextPoint = new MyPoint(-1, -1);
}
pointsInOneRow.add(
currentPoint); // add current point to a list of points, that lies on one line.
// if the currentPoint and the nextPoint are on the same line, that is parallel to the X axis.
while (currentPoint.getY() == nextPoint.getY()) {
pointsInOneRow.add(
nextPoint); // add the nextPoint to a list of points, that lies on one line.
itr.remove(); // delete the second element from the randomListOfPoints .
currentPoint = nextPoint; // the currentPoint equals to the nextPoint now.
if (itr.hasNext()) { // if it's not the end of the randomListOfPoints.
nextPoint = itr.next(); // the second element from the randomListOfPoints.
} else {
// the point not from the range of possible Xs and Ys, so we can be sure that its' Y won't
// be equal to the currentPoints'.
nextPoint = new MyPoint(-1, -1);
}
}
Collections.sort(
pointsInOneRow, new XcoordSorterComparator()); // sort the pointsInOneRow by X
/* add all elements from the pointsInOneRow to the end of the listOfPointsToBeConnected.
* If the listOfPointsToBeConnected.size == 0 - the first element from the pointsInOneRow will be the start
* of the broken line, if the listOfPointsToBeConnected.size != 0 - the first element from the
* pointsInOneRow will be connected with the last element from the listOfPointsToBeConnected*/
listOfPointsToBeConnected.addAll(listOfPointsToBeConnected.size(), pointsInOneRow);
}
System.out.println("\n\nList of connected points:\n" + listOfPointsToBeConnected);
}
@Override
public int compare(MyPoint o1, MyPoint o2) {
return (int) o1.getY() - (int) o2.getY();
}