How to see my code drawing a line from one point to another

Question

hi, im wondering if you could help me.
i am working on my project which is to visualise travelling salesman heuristics.
i have managed to make my first heuristic work, but my problem is that when i clicked the run button on my GUI,
the output is already a complete tour with all the edges already drawn, but what i want is to see how it solves or draw the lines from one vertex to another just by clickin the run button once.
would be great if you could advice me of what method or technique i need to use to see my application solving the tour or drawing the edges.
below is my cofe for drawing the edges from one point to another
  void drawLineNNh(Graphics g){
         Graphics2D g2 = (Graphics2D) g;
         g2.setColor(Color.blue);
         int i = 0;
         if (P == null) return;
         else
             for(i=0; i<P.getSize(); i++)
             Line2D.Double drawLine = new Line2D.Double(P.x_coor[nnH.seen]+5, P.y_coor[nnH.seen[i]]+5, P.x_coor[nnH.seen[i+1]]+5,P.y_coor[nnH.seen[i+1]]+5);
Line2D.Double drawLastEdge = new Line2D.Double(P.x_coor[nnH.seen[P.getSize()-1]]+5, P.y_coor[nnH.seen[P.getSize()-1]]+5, P.x_coor[0]+5,P.y_coor[0]+5);
g2.drawString( " Total Distance : " + nnH.totalDistance , 10, 300);
g2.draw(drawLine);
g2.draw(drawLastEdge);
public void setNNh(Points p)
nnH = new NNheuristic(p);
useNNh = true;
public void paint(Graphics g)
frame(g);
drawpoints(g);
if(useNNh)
drawLineNNh(g);
below is my code for calling the above method to draw edges, actionlistererun.addActionListener(new ActionListener()
public void actionPerformed(ActionEvent e) {
if (e.getActionCommand().equals("Run")) {
if (chooseHeur.getSelectedItem()=="Nearest-Neighbour")
System.out.println(chooseHeur.getSelectedItem());
//points = new Points(toInt((String)chooseNum.getSelectedItem()));
//PlotArea.set(points);
PlotArea.setNNh(points);
PlotArea.repaint();

Answer 1

I AM USING SWING.
HERE IS MY CODE, HOPEFULLY ENOUGH TO UNDERSTAND THE PROBLEM.
class Plot extends Panel{
     public static int num;
     NNheuristic nnH;
     Closest_insertion CI;
     Points P;
     public static boolean useNNh= false;
     boolean useCI=false;
     boolean triangleDrawn = false;
     boolean CIupdate;
     void drawpoints (Graphics g)
         Graphics2D g2 = (Graphics2D) g;
         Graphics2D g3 = (Graphics2D) g;
         int i=1;
         g2.setColor(Color.red);
                if (P==null) return;
                else
                while (i<P.getSize())
                     Ellipse2D.Double vertices = new Ellipse2D.Double(P.x_coor,P.y_coor[i],10,10);
g2.fill(vertices);
i++;
g3.setColor(Color.MAGENTA);
Ellipse2D.Double initial = new Ellipse2D.Double(P.x_coor[0],P.y_coor[0],10,10);
g3.fill(initial);
System.out.println("No. of Vertices: " + P.getSize());
for(int k = 0; k < P.getSize(); k++)
System.out.println("x coordinate: " + P.x_coor[k] + ", " + "y coordinate :" + P.y_coor[k] );
// System.out.println("next:"+ P.x_coor[k+1]);
triangleDrawn = false;
void drawLineNNh(Graphics g){
Graphics2D g2 = (Graphics2D) g;
g2.setColor(Color.blue);
int i = 0;
if (P == null) return;
else
for(i=0; i<P.getSize(); i++)
Line2D.Double drawLine = new Line2D.Double(P.x_coor[nnH.seen[i]]+5, P.y_coor[nnH.seen[i]]+5, P.x_coor[nnH.seen[i+1]]+5,P.y_coor[nnH.seen[i+1]]+5);
Line2D.Double drawLastEdge = new Line2D.Double(P.x_coor[nnH.seen[P.getSize()-1]]+5, P.y_coor[nnH.seen[P.getSize()-1]]+5, P.x_coor[0]+5,P.y_coor[0]+5);
g2.drawString( " Total Distance : " + nnH.totalDistance , 10, 300);
g2.draw(drawLine);
g2.draw(drawLastEdge);
public void set (Points p)
P=p;
useNNh = false;
useCI = false;
public void setNNh(Points p)
nnH = new NNheuristic(p);
useNNh = true;
void frame (Graphics g)
g.setColor(Color.white);
          g.fillRect(0,0,size().width,size().height);
          g.setColor(Color.green);
          g.drawRect(0,0,579,280);
public void paint(Graphics g)
frame(g);
drawpoints(g);
if(useNNh)
drawLineNNh(g);
else if(useCI)
if(!CIupdate)
drawTriCI(g);
else
drawRestCI(g);
// drawLineNNh(g);
public void clear ()
     // remove the points and the graph.
P=null;
triangleDrawn = false;
code of my GUIpublic class TSP extends JFrame{
JButton run;
...................codes...........
TSP() {
...............................codes...........
run = new JButton ("Run");
run.setPreferredSize(new Dimension(113,30));
run.addActionListener(new ActionListener()
public void actionPerformed(ActionEvent e) {
if (e.getActionCommand().equals("Run")) {
if (chooseHeur.getSelectedItem()=="Nearest-Neighbour")
System.out.println(chooseHeur.getSelectedItem());
//points = new Points(toInt((String)chooseNum.getSelectedItem()));
//PlotArea.set(points);
PlotArea.setNNh(points);
PlotArea.repaint();
else if(chooseHeur.getSelectedItem()=="Closest-Insertion")
PlotArea.setC_I(points);
PlotArea.repaint();
pane2.add(run);