Graph.java

package CVRP;

//This program will read a solution to the CVRP problem from a file called best-solution.txt
//It requires the CVRPData.java file which is available on the unit web page.

//To run, ensure that the Graph.java file, the CVRPData.java file and the best-solution.txt file are all in the current directory.
//Compile using the command:
//javac Graph.java CVRPData.java
//Run using the command:
//java Graph

//This program assumes that there is only one depot, which is index 1 in CVRPData's data structure.
//It also assumes that best-solution.txt is formatted correctly (with login, cost etc)

//This code has a hack to fix a problem with coordinates. The CVRP data may have negative coordinates but this
//code will only diplay positive coordinates on screen. By adding SHIFT to each coodinate we can make them positive,
//but the value of SHIFT needs to be set for each problem. (We could set it automatically by looking at the coordinates
//but I haven't bothered.

//@author Thomas Pickering
//@author Tim Kovacs

import java.awt.*;
import javax.swing.*;
import java.util.ArrayList;
import java.util.Random;
import java.io.*;

//Class Description:
//Draws a graph of a given solution.

public class Graph extends JPanel {

// ******************* Constants ************************

public static int WIDTH;
public static int HEIGHT;
public static final int PADDING        = 40;
public static final int SCALE_FACTOR   = 5;
public static final int CROSS_SIZE     = 3;
public static final int LINE_THICKNESS = 3;
public static final Color AXIS_COLOUR  = Color.BLACK;
public static final Color DEPOT_COLOUR = Color.RED;
public static final Color POINT_COLOUR = Color.BLACK;
public static final int SHIFT = 100; // add this to all coordinates to make them positive

// ******************** Fields **************************

// Window
JFrame w;

ArrayList<ArrayList<Integer>> trucks;
ArrayList<Color> truckColours;

FileInputStream inStream; // = new FileInputStream("best-solution.txt");
DataInputStream dStream;
BufferedReader reader;

// ***************** Constructors ***********************


public Graph() {
 CVRPData.readFile("fruitybun250.vrp");
 trucks = new ArrayList<ArrayList<Integer>>();

 setWidthAndHeight();
 truckColours = new ArrayList<Color>();
 setupWindow();
 readFile();
 generateColours();
 repaint();
}

// ******************* Methods **************************

 /** Return a Point representing the coordinates of the given Node
  * and add SHIFT to each dimension in order to make them positive */
 private Point getLocation(int node) {
	Point aPoint = CVRPData.getLocation(node);
	int x = (int) aPoint.getX() + SHIFT;
	int y = (int) aPoint.getY() + SHIFT;
	aPoint.setLocation(x,y);
	return aPoint;
 }

// Sets the WIDTH and HEIGHT constants.
private void setWidthAndHeight() {
 int maxX = (int) Double.NEGATIVE_INFINITY;
 int maxY = (int) Double.NEGATIVE_INFINITY;

 int xPos, yPos;

 for (int i = 1; i < CVRPData.NUM_NODES; i++) {
   xPos = (int) getLocation(i).getX();
   yPos = (int) getLocation(i).getY();

   if (xPos > maxX) maxX = xPos;
   if (yPos > maxY) maxY = yPos;
 }

 WIDTH  = maxX * SCALE_FACTOR;
 HEIGHT = maxY * SCALE_FACTOR;
}


private void readFile() {
 ArrayList<Integer> route = new ArrayList<Integer>();

 try {
   inStream = new FileInputStream("best-solution.txt");
   dStream = new DataInputStream(inStream);
   reader = new BufferedReader(new InputStreamReader(inStream));

   String line;
   String delim = "->";

   while ((line = reader.readLine()) != null) {
     route = new ArrayList<Integer>();

	if (line.startsWith("login") || line.startsWith("name") || line.startsWith("algorithm") || line.startsWith("cost"))
	    continue;

	String[] tokens = line.split(delim);
	for (int i = 0; i < tokens.length; i++) {
	    route.add(new Integer(tokens[i]));	
	}
	  trucks.add(route);
   }
   
 } catch (FileNotFoundException e) {
   System.err.println("Error: best-solution.txt not found.");
 } catch (IOException e) {
   System.err.println("Error whilst reading from best-solution.txt. Is it formatted correctly?");
 }
}
/*

// Entry point
public static void main(String[] args) {
 new Graph();
}

*/
// Sets up the graph window
private void setupWindow() {
 w = new JFrame("Best Solution");
 w.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
 w.setLocationByPlatform(true);
 w.add(this);
 w.setSize(new Dimension(WIDTH + (2 * PADDING), HEIGHT + (2 * PADDING)));
 w.setVisible(true);
}


private void generateColours() {
 Random g = new Random();

 for (int i = 0; i < trucks.size(); i++) {
   truckColours.add(new Color(g.nextInt(255), g.nextInt(255), g.nextInt(255)));
 }
}


protected void paintComponent(Graphics g) {
 //g.super();
 Graphics2D g2d = (Graphics2D) g;

 g2d.setStroke(new BasicStroke(LINE_THICKNESS));
 //drawAxes(g2d);

 // Draw trucks
 for (int i = 0; i < trucks.size(); i++) {
   for (int j = 0; j < trucks.get(i).size() - 1; j++) {
	int x1 = ((int) getLocation(trucks.get(i).get(j).intValue()).getX()     * SCALE_FACTOR) + PADDING;
	int y1 = HEIGHT - ((int) getLocation(trucks.get(i).get(j).intValue()).getY()     * SCALE_FACTOR) + PADDING;
	int x2 = ((int) getLocation(trucks.get(i).get(j + 1).intValue()).getX() * SCALE_FACTOR) + PADDING;
	int y2 = HEIGHT - ((int) getLocation(trucks.get(i).get(j + 1).intValue()).getY() * SCALE_FACTOR) + PADDING;

	g2d.setColor(truckColours.get(i));
     g2d.drawLine(x1, y1, x2, y2);
   }
 }

 // Draw depot
 drawX(g2d, DEPOT_COLOUR, getLocation(1));

 // Draw customers
 for (int i = 2; i < CVRPData.NUM_NODES; i++) {
   drawX(g2d, POINT_COLOUR, getLocation(i));
 }
}


// Draws the graph axes
private void drawAxes(Graphics2D g) {
 g.setColor(AXIS_COLOUR);

 g.drawLine(PADDING, PADDING, PADDING, PADDING + HEIGHT);
 g.drawLine(PADDING, PADDING + HEIGHT, PADDING + WIDTH, PADDING + HEIGHT);
}


// Draws an 'x' at a given point in a given colour.
protected void drawX(Graphics2D g, Color c, Point p) {
 int x = (((int) p.getX()) * SCALE_FACTOR) + PADDING;
 int y = PADDING + HEIGHT - (((int) p.getY()) * SCALE_FACTOR);

 g.setColor(c);

 g.drawLine(x - CROSS_SIZE, y - CROSS_SIZE, x + CROSS_SIZE, y + CROSS_SIZE);
 g.drawLine(x - CROSS_SIZE, y + CROSS_SIZE, x + CROSS_SIZE, y - CROSS_SIZE); 
}
}