Source Code for Course-Selector

courses.txt

TB2	CS-306	10	Writing Mobile Apps
TB1	CS-307	10	Computer Graphics II:Modelling and Rendering
TB2	CS-311	10	Concepts of Programming Languages
TB1	CS-313	10	High Integrity Systems
TB2	CS-318	10	Cryptography and IT Security
TB1	CS-337	10	Data Visualization
TB2	CS-338	10	Internet Computing
TB1	CS-345	10	Artificial Intelligence Applications
TB2	CS-348	10	Building Reliable Web Applications
TB2	CS-349	10	Mobile Interaction Design
TB1	CS-358	10	High-Performance Computing in C/C++
TB2	CS-364	10	Software Testing
TB1	CS-368	10	Embedded Systems
TB2	CS-371	10	Design Patterns and Generic Programming
TB1	CS-375	10	Logic for Computer Science
TB1	CS-377	10	Computer Vision and Pattern Recognition
TB1	CS-390	10	Teaching Computing via a School Placement

DataNode.java

/**
 * Represents a course
 * 
 * @author Joss
 * 
 */
public class DataNode {

	// Constants
	public static final int TB1 = 1, TB2 = 2;
	private static final float BASE_RANK = 1400;

	// Members
	private int m_set, m_credits, m_wins = 0, m_losses = 0;
	private String m_code, m_name;
	private float m_rank;

	/**
	 * Constructor
	 * 
	 * @param set
	 *            TB1 or TB2
	 * @param code
	 *            The module code
	 * @param name
	 *            The module name
	 * @param credits
	 *            The credits associated with the module
	 */
	public DataNode(int set, String code, String name, int credits) {
		m_set = set;
		m_code = code;
		m_name = name;
		m_credits = credits;

		m_rank = BASE_RANK;

		System.out.println(getString());
	}

	// Accessor / Mutator

	public String getString() {
		return "(" + m_rank + " - " + m_wins + "/" + m_losses + ") " + (m_set == TB1 ? "TB1" : "TB2") + " " + m_code
				+ " " + m_credits + " " + m_name;
	}

	public int getSet() {
		return m_set;
	}

	public int getCredits() {
		return m_credits;
	}

	public String getCode() {
		return m_code;
	}

	public String getName() {
		return m_name;
	}

	public float getRank() {
		return m_rank;
	}

	public void setRank(float rank) {
		m_rank = rank;
	}

	public int getWins() {
		return m_wins;
	}

	public int getLosses() {
		return m_losses;
	}

	public int win() {
		m_wins++;
		return m_wins;
	}

	public int lose() {
		m_losses++;
		return m_losses;
	}
}

DNListRenderer.java

import java.awt.Color;
import java.awt.Component;
import java.awt.Dimension;
import java.awt.Font;
import java.awt.Graphics;
import java.awt.Graphics2D;
import java.awt.RenderingHints;

import javax.swing.JList;
import javax.swing.JPanel;
import javax.swing.ListCellRenderer;

/**
 * Renders the JList of DNodes
 * 
 * @author Joss
 * 
 */
public class DNListRenderer extends JPanel implements ListCellRenderer {

	// Constants
	private static final int WIDTH = 200;
	private static final int HEIGHT = 25;

	private static final float FONT_SIZE = 10.0f;
	private static final int TEXT_X = 5;
	private static final int TEXT_Y = 15;
	private static final Color TEXT_COLOUR = new Color(34, 34, 34);
	private static final Color BACKGROUND_COLOUR = new Color(245, 245, 245);
	private static final Color SELECTED_COLOUR = new Color(200, 200, 200);

	// Members
	private DataNode m_value;
	private boolean m_selected;

	/**
	 * Gets the component of the cell to be displayed
	 * 
	 * @param list
	 *            The JList the cell belongs to
	 * @param value
	 *            The value stored in the JList for this cell
	 * @param index
	 *            The index this cell is at in the JList
	 * @param isSelected
	 *            Is the current cell selected
	 * @param cellHasFocus
	 *            Does the cell have focus
	 * @return The component to be rendered (This class)
	 */
	public Component getListCellRendererComponent(JList list, Object value, int index, boolean isSelected,
			boolean cellHasFocus) {

		setPreferredSize(new Dimension(WIDTH, HEIGHT));

		m_selected = isSelected;
		m_value = (DataNode) value;

		repaint();
		return this;
	}

	/**
	 * Renders the header cell
	 * 
	 * @param g
	 *            The graphics hook passed in by the system
	 */
	protected void paintComponent(Graphics g) {
		super.paintComponent(g);

		Graphics2D g2 = (Graphics2D) g;

		RenderingHints rh = new RenderingHints(RenderingHints.KEY_ANTIALIASING, RenderingHints.VALUE_ANTIALIAS_ON);
		rh.put(RenderingHints.KEY_TEXT_ANTIALIASING, RenderingHints.VALUE_TEXT_ANTIALIAS_ON);
		rh.put(RenderingHints.KEY_RENDERING, RenderingHints.VALUE_RENDER_QUALITY);
		g2.setRenderingHints(rh);

		int w = getWidth(), h = getHeight();
		Font stdFont = g2.getFont();

		g2.setColor((!m_selected) ? BACKGROUND_COLOUR : SELECTED_COLOUR);
		g2.fillRect(0, 0, w, h);

		g2.setColor(TEXT_COLOUR);
		g2.setFont(stdFont.deriveFont(FONT_SIZE));
		g2.drawString(m_value.getString(), TEXT_X, TEXT_Y);

		g2.dispose();
	}
}

GUI_Main.java

import java.awt.BorderLayout;
import java.awt.Dimension;
import java.awt.EventQueue;
import java.awt.event.ActionEvent;
import java.awt.event.ActionListener;
import java.io.File;
import java.net.URI;
import java.util.ArrayList;
import java.util.Scanner;

import javax.swing.JButton;
import javax.swing.JFrame;
import javax.swing.JList;
import javax.swing.JPanel;
import javax.swing.JScrollPane;
import javax.swing.JSplitPane;
import javax.swing.ScrollPaneConstants;
import javax.swing.UIManager;
import javax.swing.border.TitledBorder;

/**
 * Main Application Window
 * 
 * @author Joss
 * 
 */
public class GUI_Main {

	// Constants
	private static final int LEFT = 1, RIGHT = 2;
	private static final int K = 16;

	// Members
	private JFrame frmModuleRanking;
	private JButton m_btnLeft;
	private JButton m_btnRight;
	private JList m_list1;
	private JList m_list2;

	private int m_curLeft, m_curRight, m_curSet;
	private ArrayList<DataNode> m_setLeft, m_setRight;

	/**
	 * Launch the application.
	 */
	public static void main(String[] args) {
		EventQueue.invokeLater(new Runnable() {
			public void run() {
				try {
					GUI_Main window = new GUI_Main();
					window.frmModuleRanking.setVisible(true);
				} catch (Exception e) {
					e.printStackTrace();
				}
			}
		});
	}

	/**
	 * Create the application.
	 */
	public GUI_Main() {
		initialize();
		loadData("resources/courses.txt");
	}

	/**
	 * Loads the data to be voted on
	 * 
	 * @param dir
	 *            The url to the data file
	 */
	private void loadData(String dir) {

		m_setLeft = new ArrayList<DataNode>();
		m_setRight = new ArrayList<DataNode>();

		try {
			File f = new File(new URI(GUI_Main.class.getResource(dir).toString()).getPath());

			Scanner inLine = new Scanner(f);

			while (inLine.hasNext()) {
				String line = inLine.nextLine();

				int set = DataNode.TB1;
				if (line.startsWith("TB2")) {
					set = DataNode.TB2;
				}

				String code = line.substring(4, 10);

				int credits = Integer.parseInt(line.substring(11, 13));

				String name = line.substring(14);

				DataNode d = new DataNode(set, code, name, credits);

				if (set == DataNode.TB1) {
					m_setLeft.add(d);
				} else {
					m_setRight.add(d);
				}

			}
		} catch (Exception e) {
			e.printStackTrace();
		}

		updateLeft();
		updateRight();

		poseQuestion();
	}

	/**
	 * Randomly select a set and two unique datanodes from that set
	 */
	private void poseQuestion() {
		m_curSet = (((int) Math.floor(Math.random() * Math.random() * 1000 / Math.random()) % 2 == 0) ? LEFT : RIGHT);

		m_curLeft = (int) Math.floor(Math.random() * (m_curSet == LEFT ? m_setLeft.size() : m_setRight.size()));

		do {
			m_curRight = (int) Math.floor(Math.random() * (m_curSet == LEFT ? m_setLeft.size() : m_setRight.size()));
		} while (m_curLeft == m_curRight);

		m_btnLeft.setText((m_curSet == LEFT ? m_setLeft.get(m_curLeft).getString() : m_setRight.get(m_curLeft)
				.getString()));
		m_btnRight.setText((m_curSet == LEFT ? m_setLeft.get(m_curRight).getString() : m_setRight.get(m_curRight)
				.getString()));
	}

	/**
	 * Voting algorithm
	 * 
	 * @param v
	 *            The vote direction
	 */
	private void vote(int v) {

		int idA = 0, idB = 0;
		ArrayList<DataNode> set = (m_curSet == LEFT ? m_setLeft : m_setRight);

		if (v == LEFT) {
			idA = m_curLeft;
			idB = m_curRight;
		} else if (v == RIGHT) {
			idB = m_curLeft;
			idA = m_curRight;
		}

		float Ra = set.get(idA).getRank();
		float Rb = set.get(idB).getRank();

		float ea = (float) (1.0f / (1.0f + (Math.pow(10.0f, ((Rb - Ra) / 400.0f)))));
		float eb = (float) (1.0f / (1.0f + (Math.pow(10.0f, ((Ra - Rb) / 400.0f)))));

		float RaN = Ra + (K * (1.0f - ea));
		float RbN = Rb + (K * (0.0f - eb));

		set.get(idA).win();
		set.get(idA).setRank(RaN);

		set.get(idB).lose();
		set.get(idB).setRank(RbN);

		if (m_curSet == LEFT) {
			m_setLeft = sortResults(set);

			updateLeft();

		} else {
			m_setRight = sortResults(set);

			updateRight();
		}

		poseQuestion();
	}

	/**
	 * Update the left list
	 */
	private void updateLeft() {
		try {
			m_list1.setListData(m_setLeft.toArray());
		} catch (Exception ex) {

		}

		m_list1.setCellRenderer(new DNListRenderer());
		m_list1.setSelectedIndex(0);
		m_list1.repaint();
	}

	/**
	 * Update the right list
	 */
	private void updateRight() {
		try {
			m_list2.setListData(m_setRight.toArray());
		} catch (Exception ex) {

		}

		m_list2.setCellRenderer(new DNListRenderer());
		m_list2.setSelectedIndex(0);
		m_list2.repaint();
	}

	/**
	 * Merge sort for lists of DataNodes, sorts by getRank() DESC
	 * 
	 * @param in
	 *            The unordered list
	 * @return The ordered list
	 */
	private ArrayList<DataNode> sortResults(ArrayList<DataNode> in) {
		if (in.size() > 1) {
			ArrayList<DataNode> in1 = new ArrayList<DataNode>(), in2 = new ArrayList<DataNode>();
			for (int i = 0; i < in.size() / 2; i++) {
				in1.add(in.get(i));
			}

			for (int i = in1.size(); i < in.size(); i++) {
				in2.add(in.get(i));
			}

			in1 = sortResults(in1);
			in2 = sortResults(in2);

			ArrayList<DataNode> out = new ArrayList<DataNode>();

			int i = 0, j = 0;
			for (int k = 0; k < in.size(); k++) {
				if (i < in1.size() && j < in2.size()) {

					if (in1.get(i).getRank() > in2.get(j).getRank()) {
						out.add(in1.get(i));
						i++;
					} else {
						out.add(in2.get(j));
						j++;
					}

				} else if (i < in1.size()) {
					out.add(in1.get(i));
					i++;
				} else if (j < in2.size()) {
					out.add(in2.get(j));
					j++;
				}

			}

			return out;
		}
		return in;
	}

	/**
	 * Initialize the contents of the frame.
	 */
	private void initialize() {

		try {
			UIManager.setLookAndFeel(UIManager.getSystemLookAndFeelClassName());
		} catch (Exception ex) {
			// Oh well... guess it will have to be ugly
		}

		frmModuleRanking = new JFrame();
		frmModuleRanking.setTitle("Module Ranking - Joss Whittle");
		frmModuleRanking.setResizable(false);
		frmModuleRanking.setBounds(100, 100, 700, 600);
		frmModuleRanking.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);

		JPanel panel = new JPanel();
		panel.setBorder(new TitledBorder(null, "Vote", TitledBorder.LEADING, TitledBorder.TOP, null, null));
		panel.setPreferredSize(new Dimension(10, 100));
		panel.setMinimumSize(new Dimension(10, 100));
		frmModuleRanking.getContentPane().add(panel, BorderLayout.NORTH);
		panel.setLayout(null);

		m_btnLeft = new JButton("Left");
		m_btnLeft.addActionListener(new ActionListener() {
			public void actionPerformed(ActionEvent e) {
				vote(LEFT);
			}
		});
		m_btnLeft.setBounds(10, 21, 335, 68);
		panel.add(m_btnLeft);

		m_btnRight = new JButton("Right");
		m_btnRight.addActionListener(new ActionListener() {
			public void actionPerformed(ActionEvent e) {
				vote(RIGHT);
			}
		});
		m_btnRight.setBounds(349, 21, 335, 68);
		panel.add(m_btnRight);

		JPanel panel_1 = new JPanel();
		panel_1.setBorder(new TitledBorder(null, "Selections", TitledBorder.LEADING, TitledBorder.TOP, null, null));
		frmModuleRanking.getContentPane().add(panel_1, BorderLayout.CENTER);
		panel_1.setLayout(new BorderLayout(0, 0));

		JSplitPane splitPane = new JSplitPane();
		splitPane.setFocusable(false);
		splitPane.setEnabled(false);
		panel_1.add(splitPane, BorderLayout.CENTER);

		JScrollPane scrollPane = new JScrollPane();
		scrollPane.setHorizontalScrollBarPolicy(ScrollPaneConstants.HORIZONTAL_SCROLLBAR_NEVER);
		scrollPane.setVerticalScrollBarPolicy(ScrollPaneConstants.VERTICAL_SCROLLBAR_ALWAYS);
		scrollPane.setPreferredSize(new Dimension(340, 2));
		scrollPane.setMinimumSize(new Dimension(340, 23));
		scrollPane.setMaximumSize(new Dimension(340, 32767));
		splitPane.setLeftComponent(scrollPane);

		m_list1 = new JList();
		scrollPane.setViewportView(m_list1);

		JScrollPane scrollPane_1 = new JScrollPane();
		scrollPane_1.setHorizontalScrollBarPolicy(ScrollPaneConstants.HORIZONTAL_SCROLLBAR_NEVER);
		scrollPane_1.setVerticalScrollBarPolicy(ScrollPaneConstants.VERTICAL_SCROLLBAR_ALWAYS);
		scrollPane_1.setMaximumSize(new Dimension(340, 32767));
		scrollPane_1.setMinimumSize(new Dimension(340, 23));
		scrollPane_1.setPreferredSize(new Dimension(340, 2));
		splitPane.setRightComponent(scrollPane_1);

		m_list2 = new JList();
		scrollPane_1.setViewportView(m_list2);
	}
}