Εκτενές παράδειγμα

Διομήδης Σπινέλλης
Τμήμα Διοικητικής Επιστήμης και Τεχνολογίας
Οικονομικό Πανεπιστήμιο Αθηνών
dds@aueb.gr

Γιορτινή κάρτα

Ολοκληρωμένο παράδειγμα

Κληρονομικότητα, δυναμική διεκπεραίωση
Συλλογές
Νήματα
Γραφικά AWT
Ήχος MIDI
Τεκμηρίωση με JavaDoc

Διάγραμμα των κλάσεων

XmasCard

package gr.aueb.xmascard;

import java.awt.Rectangle;

/**
 * The Christmas Card program main class.
 *
 * @author Giorgos Gousios, Diomidis Spinellis
 * @depend - - - gr.aueb.xmascard.DrawPanel
 * @depend - <instantiate> - gr.aueb.xmascard.MidiPlayer
 * @depend - - - gr.aueb.xmascard.Tree
 * @depend - - - gr.aueb.xmascard.PointSnowFlake
 * @depend - - - gr.aueb.xmascard.SlashSnowFlake
 */
public class XmasCard {

    /** Number of trees */
    private static final int numTrees = 30;
    /** Number of snowflakes */
    private static final int numSnowFlakes = 1500;
    /** Minimum tree width. */
    private static final int treeWidth = 30;
    /** Minimum tree height. */
    private static final int treeHeight = 100;
    /** Additional variation to tree height and width */
    private static final int treeWobble = 100;
    /** Song to play. */
    private static String musicFile = "jbelrock.mid";

    public static void main(String[] args) {

        // Create a window and the canvas to draw onto.
        DrawPanel d = new DrawPanel();

        // Create randomly-positioned trees.
        for (int i = 0; i < numTrees; i++) {
            Rectangle treeBox = new Rectangle(
		(int)(Math.random() * DrawPanel.WIDTH),
                (int)(Math.random() * DrawPanel.HEIGHT),
                treeWidth + (int)(Math.random() * treeWobble),
                treeHeight + (int)(Math.random() * treeWobble));

            Tree t = new Tree(d.getCanvas(), treeBox);
            d.addDrawObject(t);
        }

	// Start playing music
	MidiPlayer m = new MidiPlayer(musicFile);

        // Create the snowflakes.
        for (int i = 0; i < numSnowFlakes; i++) {
	    switch (i % 6) {
	    case 0:
	    case 1:
                d.addDrawObject(new PointSnowFlake(d.getCanvas(), '.', 15));
		break;
	    case 2:
                d.addDrawObject(new PointSnowFlake(d.getCanvas(), 'o', 10));
		break;
	    case 3:
                d.addDrawObject(new PointSnowFlake(d.getCanvas(), '*', 5));
		break;
	    case 4:
	    case 5:
                d.addDrawObject(new SlashSnowFlake(d.getCanvas()));
		break;
	    }
	    try {
		// Allow existing snowflakes to fall a bit, before adding more
		Thread.sleep(100);
	    } catch (InterruptedException e) {
	    }
        }
    }
}

DrawPanel

/*- * Copyright 2005-2018 Diomidis Spinellis * * Licensed under the Apache License, Version 2.0 (the "License"); * you may not use this file except in compliance with the License. * You may obtain a copy of the License at * * http://www.apache.org/licenses/LICENSE-2.0 * * Unless required by applicable law or agreed to in writing, software * distributed under the License is distributed on an "AS IS" BASIS, * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. * See the License for the specific language governing permissions and * limitations under the License. */ package gr.aueb.card; import java.awt.Color; import java.awt.Dimension; import java.awt.event.WindowAdapter; import java.awt.event.WindowEvent; import java.util.Vector; import javax.swing.JFrame; import javax.swing.JPanel; /** * The program's main window. * Extends JFrame to display the window where the * trees and snow are drawn. Implements the {@link java.lang.Runnable Runnable} * interface so as to create a thread that repeatedly calls the * {@link gr.aueb.card.Drawable#draw() draw}method. * * @author Giorgos Gousios, Diomidis Spinellis * @opt nodefillcolor lightblue * @assoc 1 drawablePanel 1 DrawablePanel */ public class DrawPanel extends JFrame implements Runnable { /** The window's width. */ public static final int WIDTH = 1024; /** The window's height. */ public static final int HEIGHT = 768; /** The window's background color (blue). */ public static final Color BACKGROUND_COLOR = new Color(0, 153, 204); /* A table that holds the objects to be drawn */ private Vector<Drawable> drawObjects = null; /* The drawing thread (not serializable) */ private transient Thread thread; /* The canvas to draw onto */ private DrawablePanel drawablePanel = null; /** Serial number of persistant data. * Required, because JFrame implements serializable. */ static final long serialVersionUID = 1L; /** * Constructor to initialize an object with the minimal required state. * The constructor is private, as the full initialization is done * in the getInstance method. */ private DrawPanel() { super("Holiday Card"); } /** * Field initialization based on a constructed instance */ private void initialize() { drawObjects = new Vector<Drawable>(); initializeGraphics(); initializeThread(); } /** * Initialize, display the window, and start the animation. * The code here is separate from the constructor in order to * avoid the resulting "this escape". */ public static DrawPanel getInstance() { DrawPanel instance = new DrawPanel(); instance.initialize(); return instance; } /** Initialize the main window. */ private void initializeGraphics() { // Make our window look nice JFrame.setDefaultLookAndFeelDecorated(true); // Create our drawing canvas drawablePanel = new DrawablePanel(this); drawablePanel.setBackground(BACKGROUND_COLOR); drawablePanel.setPreferredSize(new Dimension(WIDTH, HEIGHT)); setContentPane(drawablePanel); // Handle termination setDefaultCloseOperation( javax.swing.WindowConstants.DISPOSE_ON_CLOSE); // Exit when the window is closed addWindowListener(new WindowAdapter() { public void windowClosing(WindowEvent e) { System.exit(0); } }); // Our size setSize(WIDTH, HEIGHT); // Force the parent window to expand the canvas to all available space pack(); //Display the window setVisible(true); } /** Start the execution of the drawing thread. */ private void initializeThread() { if (thread == null) { thread = new Thread(this); thread.setPriority(Thread.MIN_PRIORITY); thread.start(); } } /** Add a component to be drawn. */ public void addDrawObject(Drawable drawObject) { drawObjects.add(drawObject); } /** Return a copy of the component list to be drawn */ public Vector<Drawable> getDrawables() { return new Vector<Drawable>(drawObjects); } /** * The method to be executed by the running thread. Executes the * {@link DrawablePanel#repaint()}method periodically. */ public void run() { Thread me = Thread.currentThread(); // Allow termination by setting thread to null while (thread == me) { // tell drawablePanel to repaint its contents drawablePanel.repaint(); try { Thread.sleep(250); } catch (InterruptedException e) { } } thread = null; } /** * Get the canvas's drawing panel * * @return javax.swing.JPanel */ public JPanel getCanvas(){ return drawablePanel; } }

Drawable

DrawablePanel

Tree

/*- * Copyright 2005-2018 Diomidis Spinellis * * Licensed under the Apache License, Version 2.0 (the "License"); * you may not use this file except in compliance with the License. * You may obtain a copy of the License at * * http://www.apache.org/licenses/LICENSE-2.0 * * Unless required by applicable law or agreed to in writing, software * distributed under the License is distributed on an "AS IS" BASIS, * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. * See the License for the specific language governing permissions and * limitations under the License. */ package gr.aueb.card; import java.awt.Color; import java.awt.Graphics; import java.awt.Polygon; import java.awt.Rectangle; import javax.swing.JPanel; /** * A self-drawable tree. Uses a box to specify the tree's bounds (the dimensions * constructor parameter). The trunk is placed in the middle of the bottom side * of the box, having a width equal to the 8% of the total width of the tree and * a height equal to the 20% of the total height of the bounding box. The main * body is represented as an isosceles triangle with a height of 80% of the * height of the bounding box. * * @author Giorgos Gousios, Diomidis Spinellis * @opt nodefillcolor green */ public class Tree extends Drawable { /** Tree trunk width as % of the bounding rectangle width */ private final double TRUNK_WIDTH_FACTOR = 0.08; /** Tree trunk height as % of the bounding rectangle height */ private final double TRUNK_HEIGHT_FACTOR = 0.2; /** Tree body height as % of the bounding rectangle height */ private final double BODY_HEIGHT_FACTOR = 0.8; /** Trunk's color (RGB) */ private final Color BROWN = new Color(204, 102, 0); /** Body's color (RGB) */ private final Color GREEN = new Color(0, 254, 0); /** Tree balls' color (RGB) */ private final Color RED = new Color(250, 0, 0); /** The tree's bounding rectangle */ private Rectangle dimensions; /** * Creates a tree from the specified bounding box * * @param panel The panel to draw the object onto * @param dimensions The bounding box dimensions. */ public Tree(JPanel panel, Rectangle dimensions) { super(panel); this.dimensions = dimensions; } /** * Draws the tree. * * @param g The Graphics object on which we will paint */ @Override public void draw(Graphics g) { drawTrunk(g); drawBody(g); } /** * Draws the trunk. For details on how the lengths are calculated * * @param g The Graphics object on which we will paint * @see gr.aueb.Tree the class description. */ private void drawTrunk(Graphics g) { /* Calculate the trunk rectangle first */ Rectangle r = new Rectangle(); r.x = (int) (dimensions.x + (dimensions.width - dimensions.width * TRUNK_WIDTH_FACTOR) / 2); r.y = (int) (dimensions.y + dimensions.height * BODY_HEIGHT_FACTOR); r.width = (int) (dimensions.width * TRUNK_WIDTH_FACTOR); r.height = (int) (dimensions.height * TRUNK_HEIGHT_FACTOR); /* Draw it! */ g.drawRect(r.x, r.y, r.width, r.height); /* Fill it with brown color */ Color c = g.getColor(); g.setColor(BROWN); g.fillRect(r.x, r.y, r.width, r.height); g.setColor(c); //Revert paint color to default } /** * Draws the body. For details on how the lengths are calculated * * @param g The Graphics object on which we will paint * @see gr.aueb.Tree the class description. */ private void drawBody(Graphics g) { /* Create the polygon (triangle) to draw */ Polygon p = new Polygon(); p.addPoint(dimensions.x + dimensions.width / 2, dimensions.y); p.addPoint(dimensions.x, (int) (dimensions.y + dimensions.height * BODY_HEIGHT_FACTOR)); p.addPoint(dimensions.x + dimensions.width, (int) (dimensions.y + dimensions.height * BODY_HEIGHT_FACTOR)); /* Draw the body */ g.drawPolygon(p); /* Fill it with green color */ Color c = g.getColor(); g.setColor(GREEN); g.fillPolygon(p); g.setColor(c); // Revert paint color to default /* Set Ornaments to the body. */ drawTreeOrnaments(g); } /** * Draws the ornaments of the tree. * @param g The Graphics object on which we will paint * @param x The Abscissa of the part of the body to draw the ornament * @param y The Ordinate of the part of the body to draw the ornament */ private void addTreeOrnament(Graphics g, int x, int y) { /* Draw Tree Ornament. */ g.drawOval(x, y, 10, 10); /* Set color to Red. */ g.setColor(RED); /* Fill Tree Ornament with color. */ g.fillOval(x, y, 10, 10); } /** * Calls addTreeOrnament for specific locations on * the tree body. * @param g The Graphics object on which we will paint */ private void drawTreeOrnaments(Graphics g) { /* yAxis of the body. */ int yAxis = (int) (dimensions.y + dimensions.height * BODY_HEIGHT_FACTOR); /* Add ornament to down left. */ addTreeOrnament(g, dimensions.x - 2, yAxis - 2); /* Add ornament to down right. */ addTreeOrnament(g, dimensions.x + dimensions.width - 1, yAxis - 1); /* Add ornament to up left. */ addTreeOrnament(g, dimensions.x + dimensions.width / 2 - 5 - 20, yAxis - 25); /* Add ornament to up right. */ addTreeOrnament(g, dimensions.x + dimensions.width / 2 - 5 + 20, yAxis - 25); /* Add ornament to middle. */ addTreeOrnament(g,dimensions.x + dimensions.width / 2 - 5, yAxis - 65); } }

SnowFlake

SlashSnowFlake

PointSnowFlake

MidiPlayer

Τεκμηρίωση

Τα σχόλια μέσα στον κώδικα επιτρέπουν την αυτόματη δημιουργία της τεκμηρίωσης, με τη χρήση του προγράμματος javadoc.
Τεκμηρίωση σε μορφή XML

Προαιρετική άσκηση

Με βάση τον κώδικα της κάρτας υλοποιήστε ένα παιγνίδι (π.χ. απόφυγε το χιόνι, ή μάζεψε τις μπάλες, ή πιάσε τον τάρανδο, κ.λπ.).

Η υλοποίηση αυτή μπορεί να γίνει από ομάδες αποτελούμενες από μέχρι δύο άτομα.
Για να υπολογιστεί η προσπάθειά σας στο βαθμό του μαθήματος θα πρέπει να μπορείτε να επιδείξετε το αποτέλεσμα και τον αντίστοιχο πηγαίο κώδικα στο τέλος του μαθήματος της Δευτέρας 8-1-2024.
Μαζί σας θα πρέπει να έχετε και μια σελίδα με το όνομα και τον ΑΜ του μέλους ή των μελών της ομάδας, όπου θα αναφέρετε περιληπτικά τι προσπαθήσατε να επιτύχετε και τι αλλαγές κάνατε στον κώδικα.

Πληροφορίες για την άσκηση

Μπορείτε να κατεβάσετε τον πηγαίο κώδικα του παραδείγματος από εδώ (https://github.com/dspinellis/holiday-card).
Οδηγίες μεταγλώττισης και εκτέλεσης υπάρχουν στο αρχείο README.md
Μπορείτε να δείτε πατήματα πλήκτρων του πληκτρολογίου μέσω της κλάσης java.awt.event.KeyEvent.

Περιεχόμενα