We Keep Coding

drawImage is not applicable for the arguments

Look I'm going to be up front about this. My assignment is due soon and i've spent way too many hours trying to fix this problem with no success at all. I'm essentially clueless at what the issue is and I really dont know where to look. I have 5 classes, I will try and post them all to ensure I get the answer, I am unable to change GameManager or Goal but I am allowed to change any other class.
The problem lines are this.canvasGraphics.drawImage(player.getCurrentImage() where drawImage says it isnt applicable for the arguments
and
this.enemies[i].getX() - (this.enemies[i].getCurrentImage().getWidth() / 2),
this.enemies[i].getY() - (this.enemies[i].getCurrentImage().getHeight() / 2), null);
where getWidth and getHeight show an almost identical error
thanks in advance
import java.awt.Dimension;
import java.awt.Graphics;
import java.awt.Toolkit;
import java.awt.event.KeyEvent;
import java.awt.event.KeyListener;
import java.awt.image.BufferedImage;
import java.awt.Font;
import java.util.Random;
import javax.swing.JFrame;
import javax.swing.JOptionPane;
public class GameManager extends JFrame implements KeyListener {
private int canvasWidth;
private int canvasHeight;
private int borderLeft;
private int borderTop;
private BufferedImage canvas;
private Stage stage;
private Enemy[] enemies;
private Player player;
private Goal goal;
private Graphics gameGraphics;
private Graphics canvasGraphics;
private int numEnemies;
private boolean continueGame;
public static void main(String[] args) {
// During development, you can adjust the values provided in the brackets below
// as needed. However, your code must work with different/valid combinations
// of values.
int choice;
do{
GameManager managerObj = new GameManager(1920, 1080);
choice=JOptionPane.showConfirmDialog(null,"Play again?", "", JOptionPane.OK_CANCEL_OPTION);
}while(choice==JOptionPane.OK_OPTION);
System.exit(0);
}
public GameManager(int preferredWidth, int preferredHeight) {
int maxEnemies;
try{
maxEnemies=Integer.parseInt(JOptionPane.showInputDialog("How many enemies? (Default is 5)"));
if (maxEnemies<0)
maxEnemies=5;
}
catch (Exception e){
maxEnemies=5;
}
this.borderLeft = getInsets().left;
this.borderTop = getInsets().top;
Dimension screenSize = Toolkit.getDefaultToolkit().getScreenSize();
if (screenSize.width < preferredWidth)
this.canvasWidth = screenSize.width - getInsets().left - getInsets().right;
else
this.canvasWidth = preferredWidth - getInsets().left - getInsets().right;
if (screenSize.height < preferredHeight)
this.canvasHeight = screenSize.height - getInsets().top - getInsets().bottom;
else
this.canvasHeight = preferredHeight - getInsets().top - getInsets().bottom;
setSize(this.canvasWidth, this.canvasHeight);
setResizable(false);
setDefaultCloseOperation(EXIT_ON_CLOSE);
setVisible(true);
addKeyListener(this);
Random rng = new Random();
this.canvas = new BufferedImage(this.canvasWidth, this.canvasHeight, BufferedImage.TYPE_INT_RGB);
// Create a Stage object to hold the background images
this.stage = new Stage();
// Create a Goal object with its initial x and y coordinates
this.goal = new Goal((Math.abs(rng.nextInt()) % (this.canvasWidth)),
(Math.abs(rng.nextInt()) % this.canvasHeight));
// Create a Player object with its initial x and y coordinates
this.player = new Player((Math.abs(rng.nextInt()) % (this.canvasWidth)),
(Math.abs(rng.nextInt()) % this.canvasHeight));
// Create the Enemy objects, each with a reference to this (GameManager) object
// and their initial x and y coordinates.
this.numEnemies = maxEnemies;
this.enemies = new Enemy[this.numEnemies];
for (int i = 0; i < this.numEnemies; i++) {
this.enemies[i] = new Enemy(this, Math.abs(rng.nextInt()) % (this.canvasWidth),
Math.abs(rng.nextInt()) % this.canvasHeight);
}
this.gameGraphics = getGraphics();
this.canvasGraphics = this.canvas.getGraphics();
this.continueGame = true;
long gameStartTime=System.nanoTime();
while (this.continueGame) {
updateCanvas();
}
this.stage.setGameOverBackground();
double gameTime=(System.nanoTime()-gameStartTime)/1000000000.0;
updateCanvas();
this.gameGraphics.setFont(new Font(this.gameGraphics.getFont().getFontName(), Font.PLAIN, 50));
if (gameTime<1)
this.gameGraphics.drawString("Oops! Better luck next time...", this.canvasWidth/3, this.canvasHeight/2 - 50);
else
this.gameGraphics.drawString("You survived " + String.format("%.1f", gameTime)+ " seconds with "+this.numEnemies+" enemies!",
this.canvasWidth/4, this.canvasHeight/2 - 50);
return;
}
public void updateCanvas() {
long start = System.nanoTime();
this.goal.performAction();
// If the player is alive, this should move the player in the direction of the
// key that has been pressed
// Note: See keyPressed and keyReleased methods in the GameManager class.
this.player.performAction();
// If the enemy is alive, the enemy must move towards the Player. The Player object
// is obtained via the GameManager object that is given at the time of creating an Enemy
// object.
// Note: The amount that the enemy moves by must be much smaller than that of
// the player above or else the game becomes too hard to play.
for (int i = 0; i < this.numEnemies; i++) {
this.enemies[i].performAction();
}
if ((Math.abs(this.goal.getX() - this.player.getX()) < (this.goal.getCurrentImage().getWidth() / 2))
&& (Math.abs(this.goal.getY() - this.player.getY()) < (this.goal.getCurrentImage().getWidth() / 2))) {
for (int i = 0; i < this.numEnemies; i++) {
// Sets the image of the enemy to the "dead" image and sets its status to
// indicate dead
this.enemies[i].die();
}
// Sets the background of the stage to the finished game background.
this.stage.setGameOverBackground();
this.continueGame = false;
}
// If an enemy is close to the player or the goal, the player and goal die
int j = 0;
while (j < this.numEnemies) {
if ((Math.abs(this.player.getX() - this.enemies[j].getX()) < (this.player.getCurrentImage().getWidth() / 2))
&& (Math.abs(this.player.getY() - this.enemies[j].getY()) < (this.player.getCurrentImage().getWidth()
/ 2))) {
this.player.die();
this.goal.die();
this.stage.setGameOverBackground();
j = this.numEnemies;
this.continueGame = false;
}
else if ((Math.abs(this.goal.getX() - this.enemies[j].getX()) < (this.goal.getCurrentImage().getWidth() / 2))
&& (Math.abs(this.goal.getY() - this.enemies[j].getY()) < (this.goal.getCurrentImage().getWidth()
/ 2))) {
this.player.die();
this.goal.die();
this.stage.setGameOverBackground();
j = this.numEnemies;
this.continueGame = false;
}
j++;
}
try {
// Draw stage
this.canvasGraphics.drawImage(stage.getCurrentImage(), 0, 0, null);
// Draw goal
this.canvasGraphics.drawImage(this.goal.getCurrentImage(),
this.goal.getX() - (this.goal.getCurrentImage().getWidth() / 2),
this.goal.getY() - (this.goal.getCurrentImage().getHeight() / 2), null);
// Draw player
this.canvasGraphics.drawImage(player.getCurrentImage(),
this.player.getX() - (this.player.getCurrentImage().getWidth() / 2),
this.player.getY() - (this.player.getCurrentImage().getHeight() / 2), null);
// Draw enemies
for (int i = 0; i < this.numEnemies; i++) {
this.canvasGraphics.drawImage(this.enemies[i].getCurrentImage(),
this.enemies[i].getX() - (this.enemies[i].getCurrentImage().getWidth() / 2),
this.enemies[i].getY() - (this.enemies[i].getCurrentImage().getHeight() / 2), null);
}
} catch (Exception e) {
System.err.println(e.getMessage());
}
// Draw everything.
this.gameGraphics.drawImage(this.canvas, this.borderLeft, this.borderTop, this);
long end = System.nanoTime();
this.gameGraphics.setFont(new Font(this.gameGraphics.getFont().getFontName(), Font.PLAIN, 15));
this.gameGraphics.drawString("FPS: " + String.format("%2d", (int) (1000000000.0 / (end - start))),
this.borderLeft + 50, this.borderTop + 75);
return;
}
public Player getPlayer() {
return this.player;
}
public void keyPressed(KeyEvent ke) {
// Below, the setKey method is used to tell the Player object which key is
// currently pressed.
// The Player object must keep track of the pressed key and use it for
// determining the direction
// to move.
// Important: The setKey method in Player must not move the Player.
if (ke.getKeyCode() == KeyEvent.VK_LEFT)
this.player.setKey('L', true);
if (ke.getKeyCode() == KeyEvent.VK_RIGHT)
this.player.setKey('R', true);
if (ke.getKeyCode() == KeyEvent.VK_UP)
this.player.setKey('U', true);
if (ke.getKeyCode() == KeyEvent.VK_DOWN)
this.player.setKey('D', true);
if (ke.getKeyCode() == KeyEvent.VK_ESCAPE)
this.continueGame = false;
return;
}
#Override
public void keyReleased(KeyEvent ke) {
// Below, the setKey method is used to tell the Player object which key is
// currently released.
// The Player object must keep track of the pressed key and use it for
// determining the direction
// to move.
// Important: The setKey method in Player must not move the Player.
if (ke.getKeyCode() == KeyEvent.VK_LEFT)
this.player.setKey('L', false);
if (ke.getKeyCode() == KeyEvent.VK_RIGHT)
this.player.setKey('R', false);
if (ke.getKeyCode() == KeyEvent.VK_UP)
this.player.setKey('U', false);
if (ke.getKeyCode() == KeyEvent.VK_DOWN)
this.player.setKey('D', false);
return;
}
#Override
public void keyTyped(KeyEvent ke) {
return;
}
}
import java.awt.image.BufferedImage;
import java.io.File;
import java.io.IOException;
import javax.imageio.ImageIO;
import java.util.*;
public class Goal {
private int x;
private int y;
private BufferedImage imageCurrent;
private BufferedImage imageRunning;
private BufferedImage imageOver;
private int stepSize;
private Random rng; // Tip: Code that students write must not use randomness
public Goal(int x, int y) {
try {
this.imageRunning = ImageIO.read(new File("goal-alive.png"));
this.imageOver = ImageIO.read(new File("goal-dead.png"));
} catch (IOException e) {
e.printStackTrace();
}
this.x = x;
this.y = y;
this.stepSize = 10;
this.rng = new Random(x + y); // Tip: Code that students write (elsewhere) must not use any randomness.
this.imageCurrent = this.imageRunning;
return;
}
public void performAction() {
// The code below shows how the Goal can be moved by manipulating its x and y
// coordinates.
// Tip: Code that students write (elsewhere) must not use any randomness.
this.x += this.rng.nextInt() % stepSize;
this.y += this.rng.nextInt() % stepSize;
return;
}
public int getY() {
return this.y;
}
public int getX() {
return this.x;
}
public BufferedImage getCurrentImage() {
return this.imageCurrent;
}
public void die() {
this.imageCurrent = this.imageOver;
return;
}
}
import java.awt.Image;
public class Enemy {
private Image CurrentImage;
private int x;
private int y;
public Enemy(GameManager gameManager, int x, int y) {
}
public void performAction() {
}
public void die() {
}
public int getX() {
return this.x;
}
public int getY() {
return this.y;
}
public Image getCurrentImage() {
return CurrentImage;
}
}
import java.awt.Dimension;
public class Player {
private Dimension CurrentImage;
private int x;
private int y;
public Player(int x1, int y1) {
}
public void performAction() {
}
public int getX() {
return this.x;
}
public int getY() {
return this.y;
}
public Dimension getCurrentImage() {
return CurrentImage;
}
public void die() {
}
public void setKey(char c, boolean b) {
}
}
import java.awt.Image;
public class Stage {
public void setGameOverBackground() {
}
public Image getCurrentImage() {
return null;
}
}

Player.getCurrentImage() returns a Dimension, not an Image.

How do I paint multiple objetcs that move at different speeds in Java?

I am working on homework for class, and its late because I can't seem to understand the material despite all the research that I am doing. I am a beginner and do not know much in the way of java. Also, this is my first post so please be forgiving when you are reading this.
I am building on source code from my textbook, which I updated recently for past homework, but now I am trying to generate a class that draws multiple squares and moves those objects independently and at different speeds. They will all need to rebound off the walls as well. I followed the instructions and created two arrays that will hold the random x and y values between 1 and 10. However, I struggle with arrays and I am sure that I am not doing it correctly. So, I would love some feedback to see if I have it set up correctly.
I have a the jpanel pulling up and drawing, and as long as there is 1 square it is working fine bouncing off the walls, but things change when I draw more than one. The do not move independently and they also share the same speed. Some even disappear from time to time. This has really thrown me off. I appreciate any help!
In short, I am trying to paint new squares that all travel in different directions and at different speeds. Per the instructions we are suppose create and use a two arrays that handle the x and y values.
Here is what I have so far:
public class DotsPanel extends JPanel
{
private int delay = 15;
private final int SIZE = 7, IMAGE_SIZE = 3; // radius of each dot
private Timer timer;
private int x, y, i;
private ArrayList<Point> pointList;
static int [] xarray = new int [1000];
static int [] yarray = new int [1000];
Random rand = new Random();
//-----------------------------------------------------------------
// Constructor: Sets up this panel to listen for mouse events.
//-----------------------------------------------------------------
public DotsPanel()
{
pointList = new ArrayList<Point>();
int [] xarray = new int [1000];
int [] yarray = new int [1000];
timer = new Timer(delay, new ReboundListener());
addMouseListener (new DotsListener());
addMouseMotionListener (new DotsListener());
setBackground(Color.gray);
setPreferredSize(new Dimension(700, 500));
for(int i = 0; i < xarray.length; i++)
{
xarray[i] = rand.nextInt(7);
yarray[i] = rand.nextInt(7);
}
timer.start();
}
//-----------------------------------------------------------------
// Draws all of the dots stored in the list.
//-----------------------------------------------------------------
public void paintComponent(Graphics page)
{
super.paintComponent(page);
page.setColor(Color.BLUE);
for (Point spot : pointList)
{
page.fillRect(spot.x-SIZE, spot.y-SIZE, 25, 25);
page.drawString("Count: " + pointList.size(), 5, 15);
}
}
//*****************************************************************
// Represents the listener for mouse events.
//*****************************************************************
private class DotsListener implements MouseListener, MouseMotionListener
{
//--------------------------------------------------------------
// Adds the current point to the list of points and redraws
// the panel whenever the mouse button is pressed.
//--------------------------------------------------------------
public void mousePressed(MouseEvent event)
{
pointList.add(event.getPoint());
repaint();
}
public void mouseDragged(MouseEvent event)
{
// initially I had two xarray and yarray in here just like in
// mouseClicked
// but it did not change anything when removed
}
//--------------------------------------------------------------
// Provide empty definitions for unused event methods.
//--------------------------------------------------------------
public void mouseClicked(MouseEvent event)
{
xarray[i] = rand.nextInt(7);
yarray[i] = rand.nextInt(7);
}
public void mouseReleased(MouseEvent event) {}
public void mouseEntered(MouseEvent event) {}
public void mouseExited(MouseEvent event) {}
public void mouseMoved(MouseEvent e) {}
}
private class ReboundListener implements ActionListener
{
//--------------------------------------------------------------
// Updates the position of the image and possibly the direction
// of movement whenever the timer fires an action event.
//--------------------------------------------------------------
public void actionPerformed(ActionEvent event)
{
for (Point spot : pointList)
{
spot.x += xarray[i];
spot.y += yarray[i];
if (spot.x <= 0 || spot.x >= 700)
xarray[i] = xarray[i] * -1;
if (spot.y <= 0 || spot.y >= 500)
yarray[i] = yarray[i] * -1;
repaint();
}
}
}
}

However, I struggle with arrays and I am sure that I am not doing it correctly.
I wouldn't use Arrays.
Instead, have a Ball object manage its own state. Then you can have different color, speed, size etc for each Ball. Then when the Timer fires you just calculate the new position and repaint the Ball.
Here is an example to get you started:
import java.awt.*;
import java.awt.event.*;
import java.awt.image.*;
import java.util.*;
import javax.swing.*;
import javax.swing.Timer;
public class BallAnimation4
{
private static void createAndShowUI()
{
BallPanel panel = new BallPanel();
JFrame frame = new JFrame("BallAnimation4");
frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
frame.add( panel );
frame.setSize(800, 600);
frame.setLocationRelativeTo( null );
//frame.setExtendedState(JFrame.MAXIMIZED_BOTH);
frame.setVisible( true );
panel.addBalls(5);
panel.startAnimation();
}
public static void main(String[] args)
{
EventQueue.invokeLater(new Runnable()
{
public void run()
{
createAndShowUI();
}
});
}
}
class BallPanel extends JPanel implements ActionListener
{
private ArrayList<Ball> balls = new ArrayList<Ball>();
public BallPanel()
{
setLayout( null );
setBackground( Color.BLACK );
}
public void addBalls(int ballCount)
{
Random random = new Random();
for (int i = 0; i < ballCount; i++)
{
Ball ball = new Ball();
ball.setRandomColor(true);
ball.setLocation(random.nextInt(getWidth()), random.nextInt(getHeight()));
ball.setMoveRate(32, 32, 1, 1, true);
// ball.setMoveRate(16, 16, 1, 1, true);
ball.setSize(32, 32);
balls.add( ball );
}
}
#Override
public void paintComponent(Graphics g)
{
super.paintComponent(g);
for (Ball ball: balls)
{
ball.draw(g);
}
}
public void startAnimation()
{
Timer timer = new Timer(75, this);
timer.start();
}
public void actionPerformed(ActionEvent e)
{
move();
repaint();
}
private void move()
{
for (Ball ball : balls)
{
ball.move(this);
}
}
class Ball
{
public Color color = Color.BLACK;
public int x = 0;
public int y = 0;
public int width = 1;
public int height = 1;
private int moveX = 1;
private int moveY = 1;
private int directionX = 1;
private int directionY = 1;
private int xScale = moveX;
private int yScale = moveY;
private boolean randomMove = false;
private boolean randomColor = false;
private Random myRand = null;
public Ball()
{
myRand = new Random();
setRandomColor(randomColor);
}
public void move(JPanel parent)
{
int iRight = parent.getSize().width;
int iBottom = parent.getSize().height;
x += 5 + (xScale * directionX);
y += 5 + (yScale * directionY);
if (x <= 0)
{
x = 0;
directionX *= (-1);
xScale = randomMove ? myRand.nextInt(moveX) : moveX;
if (randomColor) setRandomColor(randomColor);
}
if (x >= iRight - width)
{
x = iRight - width;
directionX *= (-1);
xScale = randomMove ? myRand.nextInt(moveX) : moveX;
if (randomColor) setRandomColor(randomColor);
}
if (y <= 0)
{
y = 0;
directionY *= (-1);
yScale = randomMove ? myRand.nextInt(moveY) : moveY;
if (randomColor) setRandomColor(randomColor);
}
if (y >= iBottom - height)
{
y = iBottom - height;
directionY *= (-1);
yScale = randomMove ? myRand.nextInt(moveY) : moveY;
if (randomColor) setRandomColor(randomColor);
}
}
public void draw(Graphics g)
{
g.setColor(color);
g.fillOval(x, y, width, height);
}
public void setColor(Color c)
{
color = c;
}
public void setLocation(int x, int y)
{
this.x = x;
this.y = y;
}
public void setMoveRate(int xMove, int yMove, int xDir, int yDir, boolean randMove)
{
this.moveX = xMove;
this.moveY = yMove;
directionX = xDir;
directionY = yDir;
randomMove = randMove;
}
public void setRandomColor(boolean randomColor)
{
this.randomColor = randomColor;
switch (myRand.nextInt(3))
{
case 0: color = Color.BLUE;
break;
case 1: color = Color.GREEN;
break;
case 2: color = Color.RED;
break;
default: color = Color.BLACK;
break;
}
}
public void setSize(int width, int height)
{
this.width = width;
this.height = height;
}
}
}
Since your Arrays only contain the Point you want to paint you don't have any information about the speed each point should be moved at. The best you could do is create a random amount each point should be moved each time its location is changed. This would give erratic movement as each time you move a point the distance would be random.
If you want more constant speed then you would need to create a second Array to contain the distance each point should move every time.
This starts to get messy creating a new Array every time you want a new property to be unique for the object you want to paint. That is why the approach to create a custom Object with multiple properties is easier to manage.

How do I embed this into my website?

I am attempting to embed a game into my website that I programmed in java. I have no idea how to take my code from eclipse(which is what my JDE is) and put it into my website. I am using a weebly.com website. I do have several unfinished classes, I want to upload my incomplete games as well as complete just to show progress. so I ask you, how do I get this code from eclipse, to my website. Thanks for the help and the following is my code.
This is my Main class:
import java.applet.Applet;
import java.awt.Graphics;
import java.awt.Image;
public class Main extends Applet implements Runnable {
private static final long serialVersionUID = 1L;
Thread th = new Thread(this);
boolean running = true;
public int Jweidth = 400, Jheight = 400;
Image dbImage;
Graphics dbGraphics;
Bullet b;
Player p;
Enemy e, e2, e3, e4, e5, e6, e7, e8;
HealthBar hb;
NameSign ns;
Restart r;
private boolean BFire;
public void init() {
//set window size
setSize(Jweidth, Jheight);
//calls player class
p = new Player(this);
//calls healthBar
hb = new HealthBar(this, p);
//calls enemy class
e = new Enemy(this);
e2 = new Enemy(42, 0, this);
e3 = new Enemy(84, 0, this);
e4 = new Enemy(126, 0, this);
e5 = new Enemy(0, 42, this);
e6 = new Enemy(42, 42, this);
e7 = new Enemy(84, 42, this);
e8 = new Enemy(126, 42, this);
//calls bullet class
b = new Bullet(this);
//calls nameSign class
ns = new NameSign(this);
//calls Restart class
r = new Restart(this);
}
public void start() {
//starts a new thread
th.start();
}
public void stop() {
running = false;
}
public void destroy() {
running = false;
}
public void run() {
while (running) {
setBFire(b.getFire());
//calls update method from player class
p.update(this);
//calls update method from enemy class
e.update(this, p);
e2.update(this, p);
e3.update(this, p);
e4.update(this, p);
e5.update(this, p);
e6.update(this, p);
e7.update(this, p);
e8.update(this, p);
//calls update method from fire class if BFire is true
if (setBFire(true)) {
b.update(this, p);
}
//calls update method from HealthBar class
hb.update(this, p);
//calls update method from NameSign class
ns.update(this);
//calls update method from Restart class
r.update(this, p);
repaint();
//sets Thread to repeat every 17 milliseconds
try {
Thread.sleep(17);
} catch (InterruptedException e) {
e.printStackTrace();
}
}
}
//doublebuffer
public void update(Graphics g) {
dbImage = createImage(Jweidth, Jheight);
dbGraphics = dbImage.getGraphics();
paint(dbGraphics);
g.drawImage(dbImage, 0, 0, this);
}
//paint class
public void paint(Graphics g) {
//calls paint method from player class
p.paint(g, this);
//calls paint method from enemy class
e.paint(g, this);
e2.paint(g, this);
e3.paint(g, this);
e4.paint(g, this);
e5.paint(g, this);
e6.paint(g, this);
e7.paint(g, this);
e8.paint(g, this);
//calls paint method from bullet class
b.paint(g, this);
//calls paint method from healthBar class
hb.paint(g, this);
//calls paint method from nameSign class
ns.paint(g, this);
//calls paint method from Restart class
r.paint(g);
}
public int getJweidth() {
return Jweidth;
}
public int getJheight() {
return Jheight;
}
//ignore all boolean Bfire methods
public boolean isBFire() {
return BFire;
}
public boolean setBFire(boolean bFire) {
BFire = bFire;
return bFire;
}
}
This is my Enemy class:
import java.awt.*;
import java.net.URL;
public class Enemy {
//Enemy ints
private int x = 0, y = 0, speed = 2;
private URL url;
private Image Enemy;
//adds image
public Enemy(Main m){
url = m.getDocumentBase();
Enemy = m.getImage(url, "Enemy.png");
}
public Enemy(int i, int j, Main m) {
url = m.getDocumentBase();
Enemy = m.getImage(url, "Enemy.png");
x = i;
y = j;
}
//same as run method but just for the enemy
public void update(Main m, Player p){
x += speed;
if(x <= 0){
speed = 2;
y += 32;
}
else if(x > m.getJweidth() - 32){
speed = -2;
y += 32;
}
//calls collision method
collision(p);
}
//enemy player hitbox
private void collision(Player p) {
int Px = p.getX();
int Py = p.getY();
int Pr = p.getRadious();
if(Px - Pr <= x && Px + Pr >= x && Py - Pr <= y && Py + Pr >= y){
p.hit();
}
}
//Graphics for enemy
public void paint(Graphics g, Main m){
g.drawImage(Enemy, x, y, m);
}
}
This is my Bullet class (this game is a work in progress and this class isn't working, but that is just unfinished work that I will do soon)
import java.awt.Graphics;
import java.awt.Image;
import java.awt.event.KeyEvent;
import java.awt.event.KeyListener;
import java.net.URL;
public class Enemy {
//Enemy ints
private int x = 0, y = 0, speed = 2;
private URL url;
private Image Enemy;
//adds image
public Enemy(Main m) {
url = m.getDocumentBase();
Enemy = m.getImage(url, "Enemy.png");
}
public Enemy(int i, int j, Main m) {
url = m.getDocumentBase();
Enemy = m.getImage(url, "Enemy.png");
x = i;
y = j;
}
//same as run method but just for the enemy
public void update(Main m, Player p) {
x += speed;
if (x <= 0) {
speed = 2;
y += 32;
} else if (x > m.getJweidth() - 32) {
speed = -2;
y += 32;
}
//calls collision method
collision(p);
}
//enemy player hitbox
private void collision(Player p) {
int Px = p.getX();
int Py = p.getY();
int Pr = p.getRadious();
if (Px - Pr <= x && Px + Pr >= x && Py - Pr <= y && Py + Pr >= y) {
p.hit();
}
}
//Graphics for enemy
public void paint(Graphics g, Main m) {
g.drawImage(Enemy, x, y, m);
}
}
This is my Restart class(once again unfinished but on the way)
import java.awt.Graphics;
import java.awt.event.KeyEvent;
import java.awt.event.KeyListener;
public class Restart implements KeyListener {
private int x, y;
private int pHealth;
private String string = "Would you like to play again?";
private boolean restart = false;
public Restart(Main m) {
x = 600;
y = 600;
}
public void update(Main m, Player p) {
//checks if players health = 0 and if restart is true
pHealth = p.getpHealth();
if (setRestart(true && pHealth <= 0)) {
System.out.println("Restart");
x = m.Jweidth / 2 - 75;
y = m.Jheight / 2;
}
//reset ints for player
//TODO
//reset ints for enemy
//TODO
//reset ints for bullet
//TODO
//reset ints for healthbar
//TODO
}
public void paint(Graphics g) {
g.drawString(string, x, y);
}
public void keyPressed(KeyEvent e) {
switch (e.getKeyCode()) {
case KeyEvent.VK_F1: {
setRestart(true);
break;
}
}
}
public void keyReleased(KeyEvent e) {
switch (e.getKeyCode()) {
case KeyEvent.VK_F1: {
setRestart(false);
break;
}
}
}
public void keyTyped(KeyEvent arg0) {
}
//ignore all boolean methods
public boolean isRestart() {
return restart;
}
public boolean setRestart(boolean restart) {
this.restart = restart;
return restart;
}
}

You will have to use Applets to embed your Java program in a browser, or Java Web Start if you just want to start it from the web in a new window.
Some security issues may apply depending on the Java version you are using.
Here are some examples on how to do it:
https://docs.oracle.com/javase/tutorial/deployment/applet/
http://www.javatpoint.com/java-applet
And here for the Java Web Start:
https://docs.oracle.com/javase/tutorial/deployment/webstart/

You're gonna need to make a .jar file and a compiled .class file, no .java file. To implement Java code in HTML, you can use the deprecated <applet> tag, or the new <object> tag.
<object codetype="application/java" classid="java:yourclass.class" archive="yourjar.jar" width="1000" height="1000"></object>
codetype="application/java" - The type of code, use application/java.
classid="?" - Java class to run, eg. java:MyApplet.class
archive="url" - Address or filename of the Java archive file (.jar) containing the class files.
width="?" - The width of the window, in pixels.
height="?" - The height of the window, in pixels.
Just telling you, I'm not sure that it'll work.

Applet Graphic Bug?

I got this really annoying error. It's really hard to explain, but basically whenever my snake tiles (I'm coding the game "Snake") leaves the screen, I set it so it returns to the same y, but the x as 0, as the x = 0 is the leftmost part of the screen...
So yeah, hard to explain. Here's the full code:
Main Class:
package com.Code0.Snake.Main;
import java.applet.Applet;
import java.awt.Color;
import java.awt.Dimension;
import java.awt.Graphics;
import java.awt.Point;
import java.util.LinkedList;
import java.util.Random;
import com.Code0.Snake.Listeners.KeyListenerS;
import com.Code0.Snake.Threads.EventS;
public class MainS extends Applet{
//Defining vars.
public final int BOX_HEIGHT = 15;
public final int BOX_WIDTH = 15;
public final int GRID_HEIGHT = 30;
public final int GRID_WIDTH = 30;
public static final int NORTH = 1;
public static final int SOUTH = 2;
public static final int EAST = 3;
public static final int WEST = 4;
public static final int NONE = 0;
public static int direction;
public LinkedList<Point> snakeParts = new LinkedList<Point>();
public Point itemLocation = new Point();
public Graphics graphics;
int randomX;
int randomY;
int runCount = 0;
EventS events = new EventS(this);
KeyListenerS keylistener = new KeyListenerS(this);
//On Initialization
public void init(){
//Adding "Snakeparts" to the linked list.
snakeParts.add(new Point(10, 10));
snakeParts.add(new Point(10, 11));
snakeParts.add(new Point(10, 12));
this.addKeyListener(keylistener);
}
//Startup paint method.
public void paint(Graphics paramGraphics){
graphics = paramGraphics.create();
this.customInit();
this.setBackground(Color.WHITE);
this.drawAll();
}
public void customInit(){
this.runCount++;
this.setSize(new Dimension(451,451));
if(this.runCount == 2){
Thread eventThread = new Thread(events);
eventThread.start();
}
}
//Used to call all draw methods.
public void drawAll(){
Random random = new Random();
//Calling all draw methods.
this.drawGrid(graphics);
this.drawFruit(graphics,random.nextInt(GRID_WIDTH),random.nextInt(GRID_HEIGHT));
this.drawSnake(graphics);
}
public void drawGrid(Graphics paramGraphics){
paramGraphics.drawRect(0,0,BOX_WIDTH * GRID_WIDTH,BOX_HEIGHT * GRID_HEIGHT);
//Drawing horizontal lines.
for(int x = BOX_WIDTH; x < BOX_WIDTH * GRID_WIDTH; x+=BOX_WIDTH){
paramGraphics.drawLine(x,0,x,BOX_HEIGHT * GRID_HEIGHT);
}
//Drawing vertical lines.
for(int y = BOX_HEIGHT; y < BOX_HEIGHT * GRID_HEIGHT; y+=BOX_HEIGHT){
paramGraphics.drawLine(0, y, GRID_WIDTH * BOX_WIDTH,y);
}
}
public void drawSnake(Graphics paramGraphics){
paramGraphics.setColor(Color.GREEN);
for(Point point : this.snakeParts){
paramGraphics.fillRect(point.x * 15, point.y * 15, BOX_WIDTH, BOX_HEIGHT);
}
paramGraphics.setColor(Color.BLACK);
}
public void drawFruit(Graphics paramGraphics, int paramX, int paramY){
paramGraphics.setColor(Color.RED);
int tempX = paramX * 15;
int tempY = paramY * 15;
paramGraphics.fillOval(tempX, tempY, BOX_WIDTH,BOX_HEIGHT);
paramGraphics.setColor(Color.BLACK);
}
public void drawEmpty(Graphics paramGraphics, int x, int y){
paramGraphics.clearRect(x * 15, y * 15, 15, 15);
this.drawGrid(graphics);
}
}
Event Class (run on seperate thread):
package com.Code0.Snake.Threads;
import java.awt.Point;
import com.Code0.Snake.Main.MainS;
public class EventS implements Runnable{
MainS main;
int CURRENT_DIRECTION;
public EventS(MainS paramMain){
this.main = paramMain;
}
#Override
public void run() {
//Infinite loop checking the game and updating it.
while(true){
main.drawGrid(main.graphics);
Point head;
Point tail;
Point finalPoint = new Point();
switch(MainS.direction){
//If direction = north
case(MainS.NORTH):
head = main.snakeParts.getFirst();
finalPoint = new Point(head.x, head.y - 1);
main.snakeParts.push(finalPoint);
tail = main.snakeParts.getLast();
main.snakeParts.remove(tail);
main.drawSnake(main.graphics);
main.drawEmpty(main.graphics, tail.x, tail.y);
break;
//If direction = south
case(MainS.SOUTH):
head = main.snakeParts.getFirst();
finalPoint = new Point(head.x, head.y + 1);
main.snakeParts.push(finalPoint);
tail = main.snakeParts.getLast();
main.snakeParts.remove(tail);
main.drawSnake(main.graphics);
main.drawEmpty(main.graphics, tail.x , tail.y);
break;
case(MainS.WEST):
head = main.snakeParts.getFirst();
finalPoint = new Point(head.x - 1, head.y);
main.snakeParts.push(finalPoint);
tail = main.snakeParts.getLast();
main.snakeParts.remove(tail);
main.drawSnake(main.graphics);
main.drawEmpty(main.graphics, tail.x , tail.y);
break;
case(MainS.EAST):
head = main.snakeParts.getFirst();
finalPoint = new Point(head.x + 1, head.y);
main.snakeParts.push(finalPoint);
tail = main.snakeParts.getLast();
main.snakeParts.remove(tail);
main.drawSnake(main.graphics);
main.drawEmpty(main.graphics, tail.x , tail.y);
break;
case(MainS.NONE):
break;
}
if(finalPoint.x > main.GRID_WIDTH){
int totalSnakeParts = main.snakeParts.size();
main.snakeParts.clear();
for(int i = totalSnakeParts; i > 0; i--){
Point tempPoint = new Point(i - 2, finalPoint.y);
main.snakeParts.add(tempPoint);
main.drawGrid(main.graphics);
System.out.println(tempPoint);
}
main.drawSnake(main.graphics);
}
try {
Thread.currentThread().sleep((long)100);
} catch (InterruptedException e) {
e.printStackTrace();
}
}
}
}
KeyListener Class:
package com.Code0.Snake.Listeners;
import java.awt.event.KeyEvent;
import java.awt.event.KeyListener;
import com.Code0.Snake.Main.MainS;
public class KeyListenerS implements KeyListener{
MainS main;
public KeyListenerS(MainS paramMain){
this.main = paramMain;
}
#Override
public void keyPressed(KeyEvent event) {
if(event.getKeyCode() == KeyEvent.VK_UP){
if(main.direction == main.SOUTH){
return;
}
main.direction = main.NORTH;
}
if(event.getKeyCode() == KeyEvent.VK_DOWN){
if(main.direction == main.NORTH){
return;
}
main.direction = main.SOUTH;
}
if(event.getKeyCode() == KeyEvent.VK_LEFT){
if(main.direction == main.EAST){
return;
}
main.direction = main.WEST;
}
if(event.getKeyCode() == KeyEvent.VK_RIGHT){
if(main.direction == main.WEST){
return;
}
main.direction = main.EAST;
}
}
#Override
public void keyReleased(KeyEvent arg0) {
}
#Override
public void keyTyped(KeyEvent arg0) {
}
}
EDIT
Here's the link to what it looks like (the bug):
http://s15.postimg.org/8z62dy7az/Bildschirmfoto_2014_06_03_um_16_47_48.png

OK, I'll try to go through your mistakes one-by-one, but really, this is a huge mess.
You save the graphics state and call paint from a separate Thread. Now, I'm not sure about applets and AWT, but in Swing that is a huge no-no. There is a convenient repaint() method available...
You do not have any synchronization on direction. This means the model can ignore the users commands if it feels like it. Try volatile. In fact, having both all variables and your drawing code in one class is fairly bad. MVC is the way to go.
You suffer from a large amount of off-by-1 errors. If you don't know what it is - google will help you. Just to name a few places where you have them: finalPoint.x > main.GRID_WIDTH will fire one cell too late since the grid starts with 0, for(int i = totalSnakeParts; i > 0; i--){Point tempPoint = new Point(i - 2, finalPoint.y); means the first point is in a negative coordinate (when i == 1).
In your border checking logic you reset the position of all the snake points, yet you do not paint empty squares on the previous positions. You do that when processing a move, why aren't you doing it now? That is the residual squares you have left on the right.
Your border checks are doing something strange anyway. What they do is straighten out the snake and teleport it to the left edge completely instead of just moving the head there. It looks the same while the snake is only 3 squares long because of a combination of bugs in number 3, but will be apparent with a longer one (Try it!). A classic approach would be to simply set the x coordinate of the head to 0, instead of resetting everything. That will also make number 4 obsolete, since you won't have to repaint the remainders at all (there won't be any, snake doesn't teleport).

Collision detection using plain arrays and rectangles--java

I am almost done with my first little java game for my final project. It is a sidescroller where you have to shoot/avoid asteroids. My last problem is figuring out how to make my array of asteroids collide with the player's lasers. Here's what I have so far, there's an "AWT-EventQueue-0" java.lang.NullPointerException" on line 137, that I can't deal with. Any help is appreciated.
Edit: I added in my other classes, I realize it would be hard to judge the functionality of my code if I didn't show you where it came from.
package ShooterGame;
import java.applet.Applet;
import java.applet.AudioClip;
import java.awt.*;
import java.awt.event.*;
import java.util.ArrayList;
import java.util.Random;
import javax.swing.*;
public class Board extends JPanel implements ActionListener
{
Enemy[] baddies = new Enemy[10000];
Player p;
Image img;
int y;
Timer time;
boolean lost = false;
static Font font = new Font("SanSerif", Font.BOLD, 24);
public AudioClip theme, bang, laser;
static ArrayList<Enemy> enemies;
public static int score = 0;
public static int lives = 5;
public Board()
{
p = new Player();
addKeyListener(new ActionListener());
setFocusable(true);
ImageIcon i = new ImageIcon("images/background.png");
img = i.getImage();
time = new Timer(5, this);
time.start();
for(int j = 0; j < baddies.length; j++)
{
Random ran = new Random();
y = ran.nextInt(365)+1;
baddies[j]= new Enemy((100*j + 700), y, "images/asteroid.gif");
}
theme = Applet.newAudioClip(getClass().getResource("theme.mid"));
theme.play();
bang = Applet.newAudioClip(getClass().getResource("bang.wav"));
}
public void actionPerformed(ActionEvent e)
{
checkCollisions();
ArrayList<?> bullets = Player.getBullets();
for(int i = 0; i < bullets.size(); i++)
{
Bullet b = (Bullet)bullets.get(i);
if(b.isVisible() == true)
{
b.move();
}
else
{
bullets.remove(i);
}
}
p.move();
for(int i = 0; i < baddies.length; i++)
{
if(p.x > 400)
{
baddies[i].move(p.getdx());
}
}
repaint();
}
public void paint(Graphics g)
{
super.paint(g);
Graphics2D g2d = (Graphics2D) g;
if(lost)
{
g2d.drawString("You Lose!", 300, 300);
}
if((p.getX() - 590) % 2400 == 0 || (p.getX() - 590) % 2400 == 1)
{
p.nx = 0;
}
if((p.getX() - 1790) % 2400 == 0 ||(p.getX() - 1790) % 2400 == 1)
{
p.nx2 = 0;
}
g2d.drawImage(img, 685-p.nx2, 0, null);
if(p.getX() >= 590)
{
g2d.drawImage(img, 685-p.nx, 0, null);
}
g2d.drawImage(p.getImage(), p.edge, p.getY(), null);
ArrayList<?> bullets = Player.getBullets();
for(int i = 0; i < bullets.size(); i++)
{
Bullet b = (Bullet)bullets.get(i);
g2d.drawImage(b.getImg(), b.getX(), b.getY(), null);
}
for(int i = 0; i < baddies.length; i++)
{
if(baddies[i].isAlive == true)
{
g2d.drawImage(baddies[i].getImg(), baddies[i].getX(), baddies[i].getY(), null);
}
}
g2d.setColor(Color.white);
g2d.drawString("Score: " + score, 0, 320);
g2d.drawString("Lives: " + lives, 80, 320);
}
public void checkCollisions()
{
Rectangle[] rect = new Rectangle[baddies.length];
for(int i = 0; i < baddies.length; i++)
{
Enemy e = (Enemy)baddies[i];
rect[i] = e.getBounds();
}
ArrayList<?> bullets = Player.getBullets();
for (int i = 0; i < bullets.size(); i++)
{
Bullet b = (Bullet) bullets.get(i);
Rectangle b1 = b.getBounds();
if (rect[i].intersects(b1) && baddies[i].isAlive())
{
score++;
baddies[i].isAlive = false;
baddies[i].isVisible = false;
bang.play();
}
Rectangle h = p.getBounds();
if (h.intersects(rect[i]))
{
if(baddies[i].isAlive() == true)
{
lives--;
if(lives < 0)
{
lost = true;
theme.stop();
System.exit(1);
}
}
}
}
}
private class ActionListener extends KeyAdapter
{
public void keyReleased(KeyEvent e)
{
p.keyReleased(e);
}
public void keyPressed(KeyEvent e)
{
p.keyPressed(e);
}
}
}
Enemy
package ShooterGame;
import java.awt.*;
import javax.swing.ImageIcon;
public class Enemy
{
int x, y;
Image img;
boolean isAlive = true;
boolean isVisible = true;
public Enemy(int startX, int startY, String location)
{
x = startX;
y = startY;
ImageIcon l = new ImageIcon(location);
img = l.getImage();
}
public Rectangle getBounds()
{
return new Rectangle(x, y, 60, 60);
}
public int getX()
{
return x;
}
public int getY()
{
return y;
}
public boolean isAlive()
{
return isAlive;
}
public boolean isVisible()
{
return isVisible;
}
public Image getImg()
{
return img;
}
public void move(int dx)
{
x = x - dx;
}
}
Bullet
package ShooterGame;
import java.applet.Applet;
import java.awt.*;
import javax.swing.ImageIcon;
import java.applet.AudioClip;
public class Bullet
{
int x, y;
Image img;
boolean visible;
public Bullet(int startX, int startY)
{
x = startX;
y = startY;
ImageIcon newBullet = new ImageIcon("images/bullet.gif");
img = newBullet.getImage();
visible = true;
}
public Rectangle getBounds()
{
return new Rectangle(x, y, 9, 5);
}
public int getX()
{
return x;
}
public int getY()
{
return y;
}
public Image getImg()
{
return img;
}
public boolean isVisible()
{
return visible;
}
public void move()
{
x = x + 2;
if(x > 700)
{
visible = false;
}
}
public void setVisible(boolean isVisible)
{
visible = isVisible;
}
}
Player
package ShooterGame;
import java.applet.Applet;
import java.applet.AudioClip;
import java.awt.*;
import java.awt.event.KeyEvent;
import java.util.ArrayList;
import javax.swing.ImageIcon;
public class Player
{
int x, dx, y, dy, nx2, nx, edge, ceiling;
Image player;
ImageIcon ib = new ImageIcon("images/player1back.gif");
ImageIcon i = new ImageIcon("images/playerstill.gif");
ImageIcon f = new ImageIcon("images/playerforward.gif");
ImageIcon up = new ImageIcon("images/playerup.gif");
ImageIcon down = new ImageIcon("images/playerdown.gif");
public AudioClip laser;
static ArrayList<Bullet> bullets;
public Player()
{laser = Applet.newAudioClip(getClass().getResource("laser.wav"));
player = ib.getImage();
x = 75;
nx = 0;
nx2 = 685;
y = 172;
edge = 150;
ceiling = 0;
bullets = new ArrayList<Bullet>();
}
public static ArrayList<Bullet> getBullets()
{
return bullets;
}
public void fire()
{
Bullet z = new Bullet((edge + 60), (y+17));
bullets.add(z);
}
public Rectangle getBounds()
{
return new Rectangle(edge, y, 43, 39);
}
public void move()
{
y = y + dy;
if(y < ceiling)
{
y = ceiling;
}
if(y > 290)
{
y = 290;
}
if(dx != -1)
{
if(edge + dx <= 151)
{
edge = edge + dx;
}
else
{
x = x + dx;
nx2 = nx2 + dx;
nx = nx + dx;
}
}
else
{
if(edge + dx > 0)
{
edge = edge + dx;
}
}
}
public int getX()
{
return x;
}
public int getdx()
{
return dx;
}
public int getY()
{
return y;
}
public Image getImage()
{
return player;
}
public void keyPressed(KeyEvent e)
{
int key = e.getKeyCode();
if(key == KeyEvent.VK_RIGHT)
{
dx = 2;
player = f.getImage();
}
if(key == KeyEvent.VK_UP)
{
dy = -1;
player = up.getImage();
}
if(key == KeyEvent.VK_DOWN)
{
dy = 1;
player = down.getImage();
}
if(key == KeyEvent.VK_SPACE)
{
fire();
laser.play();
}
}
public void keyReleased(KeyEvent e)
{
int key = e.getKeyCode();
if(key == KeyEvent.VK_RIGHT)
{
dx = 1;
player = ib.getImage();
}
if(key == KeyEvent.VK_UP)
{
dy = 0;
player = ib.getImage();
}
if(key == KeyEvent.VK_DOWN)
{
dy = 0;
player = ib.getImage();
}
}
}
Frame
package ShooterGame;
import javax.swing.*;
public class Frame
{
public AudioClip theme;
public Frame()
{
JFrame frame = new JFrame();
frame.add(new Board());
frame.setTitle("SideShooter");
frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
frame.setSize(700,365);
frame.setVisible(true);
frame.setLocationRelativeTo(null);
}
public static void main(String[] args)
{
new Frame();
}
}

Ok, so the problem is the line mentioned in the other answer, but I believe it is that all the enemies may not be initialised before it checks collisions. Because you are making 10000 of them to start with, I think your action performed method may be checking collisions before they have all be created.
One thing to try could be to bring down the amount of enemies you have and see if it still keeps happening, try 100 or 1000, but this still won't fix the issue.
You really want to be change your game to run in it's own loop though, at the moment you are only checking collisions when the player performs an action. so if the player stops moving, no collision detection...
I would suggest that you find a book called 'Killer Game Programming in Java', there are free ebook version, and just read the first 2 chapters about making a game loop. The book is a bit old, but the basics of the loop are very good.
This question here also contains a very simple loop, and some suggestions in the comments about how to make it better.

The error is on the line
rect[i] = e.getBounds();
Are you not initializing the bounds of your Enemy class correctly? Alternatively, the Enemy you pulled out of the array could be null.