// method to print edge points out to a file
public void printEdgePointsToFile(String filename) {
try {
PrintWriter writer = new PrintWriter(filename, "UTF-8");
for (MapEdge e : edges) {
writer.println(e.getStartPoint() + " " + e.getEndPoint());
}
writer.flush();
writer.close();
} catch (Exception e) {
System.out.println("Exception opening file " + e);
}
}
