Hi, I'm developing a snake game. To create the snake I'm using ArrayList. While moving the snake I'm getting the following error: "java.lang.IndexOutOfBoundsException: Index: 3, Size: 3". Below is my program. In Snake.update() method I have problem.
Game.java:
import javax.swing.JFrame;
#SuppressWarnings("serial")
public class Game extends JFrame {
public Game(){
add(new GamePanel());
setTitle("Game Test3");
setVisible(true);
setAlwaysOnTop(true);
setLocationRelativeTo(null);
setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
pack();
}
public static void main(String[] args) {
new Game();
}
}
GamePanel.java:
import java.awt.Color;
import java.awt.Dimension;
import java.awt.Graphics2D;
import java.awt.Image;
import java.awt.RenderingHints;
import java.awt.event.KeyEvent;
import java.awt.event.KeyListener;
import javax.swing.JPanel;
#SuppressWarnings("serial")
public class GamePanel extends JPanel implements Runnable, KeyListener {
public static int width = 300;
public static int height = 400;
private Thread thread;
private Image image;
private Graphics2D g;
private Food food;
private Snake snake;
public GamePanel() {
setPreferredSize(new Dimension(width, height));
setFocusable(true);
}
public void addNotify() {
super.addNotify();
if (thread == null) {
thread = new Thread(this);
thread.start();
}
addKeyListener(this);
}
public void run() {
image = createImage(width, height);
g = (Graphics2D) image.getGraphics();
RenderingHints reneringHints = new RenderingHints(
RenderingHints.KEY_ANTIALIASING,
RenderingHints.VALUE_ANTIALIAS_ON);
g.setRenderingHints(reneringHints);
food = new Food();
snake = new Snake();
while (true) {
gameRender();
gameUpdate();
gameDraw();
try {
Thread.sleep(10);
} catch (InterruptedException e) {
e.printStackTrace();
}
}
}
private void gameDraw() {
Graphics2D g2 = (Graphics2D) getGraphics();
g2.drawImage(image, 0, 0, this);
g2.dispose();
}
private void gameRender() {
g.setColor(Color.black);
g.fillRect(0, 0, width, height);
// food drawing
food.draw(g);
// snake drawing
snake.draw(g);
}
private void gameUpdate() {
food.update();
snake.update();
}
public void keyPressed(KeyEvent e) {
int key = e.getKeyCode();
if (key == KeyEvent.VK_LEFT) {
snake.setLeft(true);
}
if (key == KeyEvent.VK_RIGHT) {
snake.setRight(true);
}
if (key == KeyEvent.VK_UP) {
snake.setUp(true);
}
if (key == KeyEvent.VK_DOWN) {
snake.setDown(true);
}
}
public void keyReleased(KeyEvent e) {
int key = e.getKeyCode();
if (key == KeyEvent.VK_LEFT) {
snake.setLeft(false);
}
if (key == KeyEvent.VK_RIGHT) {
snake.setRight(false);
}
if (key == KeyEvent.VK_UP) {
snake.setUp(false);
}
if (key == KeyEvent.VK_DOWN) {
snake.setDown(false);
}
}
public void keyTyped(KeyEvent e) {
}
}
//snake body
import java.awt.Color;
import java.awt.Graphics2D;
import java.awt.Rectangle;
import java.util.ArrayList;
public class Snake {
private int x;
private int y;
private int r;
int body;
Rectangle rectangle;
ArrayList<Rectangle> rc = new ArrayList<Rectangle>();
private boolean left;
private boolean right;
private boolean up;
private boolean down;
public Snake() {
x = 150;
y = 150;
r = 4;
body = 3;
for (int i = 0; i < body; i++) {
rc.add(new Rectangle(x - i * r * 3, y, r * 3, r * 3));
}
}
public void draw(Graphics2D g) {
for (int i = 0; i < body; i++) {
if (i == 0) {
g.setColor(Color.red);
} else {
g.setColor(Color.green);
}
g.fillOval(rc.get(i).x, rc.get(i).y, rc.get(i).width,
rc.get(i).height);
}
}
public void update() {
for (int i = body; i > 0; i--) {
rc.set(i, rc.get(i - 1));
}
if (left) {
rc.get(0).x -= 1;
System.out.println("vbnv");
}
if (right) {
rc.get(0).x += 1;
}
if (up) {
rc.get(0).y -= 1;
}
if (down) {
rc.get(0).y += 1;
}
}
public void setLeft(boolean b) {
left = b;
}
public void setRight(boolean b) {
right = b;
}
public void setUp(boolean b) {
up = b;
}
public void setDown(boolean b) {
down = b;
}
}
Without reading the code I can tell that somewhere you are trying to get non-existent element. Read the message of exception, it tells you that your ArrayList consist of three elements (which means that the last element has index of 2) while you try to get the element with index of 3.
Update: yes, the problem is here:
for (int i = body; i > 0; i--) {
rc.set(i, rc.get(i - 1));
}
body equals to 3, and rc after the constructor invocation has the size of 3. set method replaces already existing element with the specified index (see the documentation), but element with index of 3 doesn't exist. That's the cause of an exception.
Your problem is in this loop:
for (int i = body; i > 0; i--) {
rc.set(i, rc.get(i - 1));
}
During the first iteration around this loop, you will be calling:
rc.set(3, <someValue>);
3 is not a valid index in a list of length 3. The largest valid index is 2.
for (int i = body; i > 0; i--)
In this for, i is assigned with the value of body(which is 3) and it looks like your ArrayList rc has only 3 elements in it. Therefore, when you try to access the index 3 using rc.set(3, something), its giving the IndexOutOfBoundsException.
Always remember, whether it is Arrays or ArrayList, the max possible index accessible in them is always array.length - 1 and ArrayList.size() - 1.
Related
I am writing a code of game bean machine(Galton box), its mechanism that one ball fall and move randomly until it get to one of the slots (randomly) and then another ball comes doing the same thing and so on, the problem is that all balls fall at the same time which something I do not want, I want each ball to fall when the current one finishes its travel..can anyone helps me ! Thanks..
here is the code:
import java.awt.*;
import java.awt.event.*;
import java.util.ArrayList;
import java.util.Collection;
import java.util.Random;
import java.util.Scanner;
import java.lang.Iterable;
import javax.swing.*;
public class BallPanel extends JPanel {
int x=1, y=1;
Collection <Ball> ball;
public static void main(String [] args){
// create the list
SwingUtilities.invokeLater(new Runnable() {
public void run() {
JFrame frame= new JFrame("Bean game");
frame.add(new BallPanel());
frame.setSize(300,500);
frame.setLocationRelativeTo(null);
frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
frame.setVisible(true);
}
});
}
public BallPanel() {
JPanel panel = new JPanel();
ball=new ArrayList<>();
for(int i=1;i<=4;i++){
ball.add(new Ball(x,y));
x++;
y++;
}
Timer timer = new Timer(400, new ActionListener()
{
public void actionPerformed(ActionEvent e) {
for (Ball b: ball) {
b.move();repaint();
}
}
});
timer.start();
}
protected void paintComponent(Graphics g) {
super.paintComponent(g);
int raduis=10;
int i=0;
int width=(getWidth()/8);
int space=(getWidth()-8*30)/2;
g.setColor(Color.BLACK);
for(i=0;i<=8;i++){
g.drawLine(space+(30*i),getHeight()-5*(raduis) ,space+(30*i) ,getHeight() );
if(i!=0 && i!=8)
g.fillOval(space+(30*i)-5, getHeight()-5*(raduis)-5, 10, 10);
if(i==0){
g.drawLine(space,getHeight()-5*(raduis) , space+((8)*15)-(raduis/2)-15 , getHeight()-15-(5*raduis)-(30*(8-2))-raduis/2);
g.drawLine(space+((8)*15)-(raduis/2)-15 , getHeight()-15-(5*raduis)-(30*(8-2))-raduis/2 , space+((8)*15)-(raduis/2)-15 , getHeight()/2-8*8);//vertical line
}
if(i==8){
g.drawLine(space+(30*i), getHeight()-5*(raduis), space+((8)*15)+(raduis/2)+15, getHeight()-15-(5*raduis)-(30*(8-2))-raduis/2);
g.drawLine(space+((8)*15)+(raduis/2)+15 , getHeight()-15-(5*raduis)-(30*(8-2))-raduis/2 , space+((8)*15)+(raduis/2)+15 , getHeight()/2-8*8);//vertical line
}
}
int o=1;
for(i=1;i<=8-2;i++){
int k=2;
for(int j=i;j<=8-2;j++){
g.fillOval(space+((i+k)*15)-raduis/2, getHeight()-(5*raduis)-(30*o)-raduis/2, raduis, raduis);
k=k+2;
}o++;
}
for (Ball b : ball) {
b.draw(g);
}
}
public class Ball {
Random rand=new Random();
private int n;
private int raduis = 10;
private int moveRaduis=12;
private int L = 0;
private int R = 0;
private int D = 0;
int x, y;
public Ball(int x, int y){
this.x=x;
this.y=y;
}
public void draw(Graphics g) {
g.setColor(Color.RED);
g.fillOval(getWidth()/2 -raduis/2 + R + L, 0 + D , moveRaduis, moveRaduis);
}
public void move() {
n=1+rand.nextInt(100);
if(n<=51){
D+=15;
if(D<=(getHeight()-15-(5*raduis)-(30*(8-2))-raduis/2))
L=0;
else if(D>getHeight()-15-(5*raduis)-(30*(8-2))-raduis/2 && D<getHeight()-5*(raduis))
{
D+=15;
L-=15;
}
else if(D>=getHeight()-5*(raduis))
{
if(D==31*15)D-=15;
D=D;
}
}
else if (n>=51 && n<=100){
D+=15;
if(D<=getHeight()-15-(5*raduis)-(30*(8-2))-raduis/2)
R=0;
else if(D>getHeight()-15-(5*raduis)-(30*(8-2))-raduis/2 && D<getHeight()-5*(raduis))
{
D+=15;
R+=15;
}
else if(D>=getHeight()-5*(raduis)){
if(D==31*15)D-=15;
D=D;
}
}
}
}
}
So, your movement code moves all the balls on each iteration, what you need to do is have an "active" ball, for example...
private Ball activeBall;
Timer timer = new Timer(400, new ActionListener() {
public void actionPerformed(ActionEvent e) {
if (activeBall != null && activeBall.hasCompleted()) {
activeBall = null;
}
if (activeBall == null && ball.size() > 0) {
activeBall = ball.remove(0);
}
if (activeBall != null) {
activeBall.move();
repaint();
}
}
});
You'll need to add in some kind of check to determine the ball has completed it's run though
basically i have been following a Java tutorial to make a basic maze game where i generate a random maze which is saved to a file then i print it out using Jpanel however i keep getting this error when i compile.
Exception in thread "AWT-EventQueue-0" java.lang.NullPointerException
at maze.Map.getMap(Map.java:43)
at maze.Board.paint(Board.java:40)
However i am not sure why, i believe it is something to do with my Y integer but if i set it to 0 it causes my program to print out wrong(just prints the same column instead of changing rows).
I need the Y value in Map.java:43 to increase like my x value does however it provides me with the Exception error.
Code:
Map Class
package maze;
import java.awt.Image;
import java.io.File;
import java.util.*;
import javax.swing.ImageIcon;
public class Map {
private Scanner m;
private Image wall, ground;
//number of columns
private String Map[] = new String[20];
public Map() {
//sets ground to a texture
ImageIcon img = new ImageIcon("C:\\MazeGraphics\\ground.png");
ground = img.getImage();
//sets wall texture
img = new ImageIcon("C:\\MazeGraphics\\wall.png");
wall = img.getImage();
openFile();
readFile();
closeFile();
}
public Image getGround() {
// gives grass texture for screen
return ground;
}
public Image getWall() {
// gives wall texture for screen
return wall;
}
public String getMap(int x, int y) {
//compares string to find graphic to use
String index= Map[y].substring(x, x+1);
return index;
}
public void openFile() {
try {
m = new Scanner(new File("C:\\MazeGraphics\\Maze.txt"));
} catch (Exception e) {
System.out.println("Error Loading Map");
}
}
public void readFile() {
for(int i = 0; i < 20; i++)
{
while(m.hasNext()){
Map[i] = m.next();
}
}
}
public void closeFile() {
m.close();
}
}
Board Class:
package maze;
import java.awt.*;
import java.awt.event.*;
import javax.swing.*;
public class Board extends JPanel implements ActionListener {
private Timer timer;
private Map m;
private Player p;
public Board()
{
MazeGeneration maz=new MazeGeneration();
//runs Map class
m = new Map();
p = new Player();
//listens for key presses
addKeyListener(new Al());
//knows to add key listener to the frame
setFocusable(true);
timer = new Timer(25, this);
timer.start();
}
public void actionPerformed(ActionEvent e) {
repaint();
}
public void paint(Graphics g) {
super.paint(g);
//paints the board row by row
for (int y = 0; y < 20; y++)
{
for (int x = 0; x < 20; x++)
{
//places graphic depending on the letter.
if (m.getMap(x, y).equals("g"))
{
g.drawImage(m.getGround(), y * 32, x * 32, null);
}
if (m.getMap(x, y).equals("w"))
{
g.drawImage(m.getWall(), y * 32,x * 32, null);
}
}
}
g.drawImage(p.getPlayer(), p.gettileX() * 32, p.gettileY() * 32, null);
}
public class Al extends KeyAdapter {
//moving the player
public void keyPressed(KeyEvent e, char maz[][], int r, int c) {
int keycode = e.getKeyCode();
if (keycode == KeyEvent.VK_W) {
//if not a wall can move
if (!m.getMap(p.gettileX(), p.gettileY() - 1).equals("w")) {
p.move(0, -1);
}
}
if (keycode == KeyEvent.VK_S) {
if (!m.getMap(p.gettileX(), p.gettileY() + 1).equals("w")) {
p.move(0, 1);
}
}
if (keycode == KeyEvent.VK_A) {
if (!m.getMap(p.gettileX() - 1, p.gettileY()).equals("w")) {
p.move(-1, 0);
}
}
if (keycode == KeyEvent.VK_D) {
if (!m.getMap(p.gettileX() + 1, p.gettileY() ).equals("w")) {
p.move(1, 0);
}
}
}
}
}
The issue is in this code: In your readFile() method, your issue arises during reading your file:
for(int i = 0; i < 20; i++)
{
while(m.hasNext()){
Map[i] = m.next();
}
}
You are assigning the value only to the 0'th index. To explain, for the first for loop, the index i is at zero. The inner loop "iterates" through the Scanner m until there is no element next. Therefore, Map[0] contains the last element on the file.
Your solution is as follows:
int i = 0;
while (m.hasNext()) {
Map[i++] = m.next();
}
I hope this helps.
I'm trying to get the controls working for a 2D game written in Java. However, I'm encountering an odd bug in movement. Whenever I'm trying to use the up and left controls while firing (space bar), or down and right while firing, the game is unable to detect the pressing of the space bar. Below are the relevant code excerpts:
import java.awt.Image;
import java.awt.event.KeyEvent;
import java.util.ArrayList;
import javax.swing.ImageIcon;
public class Player {
private String playerPath = "images/craft.png";
private int x, y, dx, dy;
private Image image;
private ArrayList missiles;
private final int CRAFT_SIZE = 20;
public Player() {
ImageIcon ii = new ImageIcon(playerPath);
image = ii.getImage();
missiles = new ArrayList();
x = 20;
y = 20;
}
public void keyPressed(KeyEvent e) {
int key = e.getKeyCode();
if (key == KeyEvent.VK_SPACE) {
fire();
}
if (key == KeyEvent.VK_LEFT) {
dx = -1;
}
if (key == KeyEvent.VK_RIGHT) {
dx = 1;
}
if (key == KeyEvent.VK_UP) {
dy = -1;
}
if (key == KeyEvent.VK_DOWN) {
dy = 1;
}
}
public void keyReleased(KeyEvent e) {
int key = e.getKeyCode();
if (key == KeyEvent.VK_LEFT) {
dx = 0;
}
if (key == KeyEvent.VK_RIGHT) {
dx = 0;
}
if (key == KeyEvent.VK_UP) {
dy = 0;
}
if (key == KeyEvent.VK_DOWN) {
dy = 0;
}
}
public void fire() {
missiles.add(new Projectile(x + CRAFT_SIZE, y + CRAFT_SIZE/2));
}
}//end class Player
And
import java.awt.Color;
import java.awt.Graphics;
import java.awt.Graphics2D;
import java.awt.Toolkit;
import java.awt.event.ActionEvent;
import java.awt.event.ActionListener;
import java.awt.event.KeyAdapter;
import java.awt.event.KeyEvent;
import java.util.ArrayList;
import javax.swing.JPanel;
import javax.swing.Timer;
public class Game extends JPanel implements ActionListener {
private Player player;
private Timer timer;
private int winHeight;
private int winWidth;
private final int UP = KeyEvent.VK_UP;
private final int DOWN = KeyEvent.VK_DOWN;
private final int LEFT = KeyEvent.VK_LEFT;
private final int RIGHT = KeyEvent.VK_RIGHT;
private final int SPACE = KeyEvent.VK_SPACE;
public Game(int w, int h) {
addKeyListener(new TAdapter());
setBackground(Color.BLACK);
addKeyListener(new TAdapter());
setFocusable(true);
setDoubleBuffered(true);
player = new Player();
winHeight = h;
winWidth = w;
timer = new Timer(5, this);
timer.start();
}
#Override
public void paint(Graphics g) {
super.paint(g);
Graphics2D g2d = (Graphics2D) g;
g2d.drawImage(player.getImage(), player.getX(), player.getY(), this);
ArrayList proj = player.getMissiles();
for (Object p : proj) {
Projectile b = (Projectile) p;
g2d.drawImage(b.getImage(), b.getX(), b.getY(), this);
}
Toolkit.getDefaultToolkit().sync();
g.dispose();
}
#Override
public void actionPerformed(ActionEvent e) {
// Update projectile locations
ArrayList ms = player.getMissiles();
for (int i = 0; i < ms.size(); i++) {
Projectile p = (Projectile) ms.get(i);
if (p.getX() <= winWidth) {
p.move();
} else {
ms.remove(p);
}
}
player.move();
repaint();
}
private class TAdapter extends KeyAdapter {
#Override
public void keyReleased(KeyEvent e) {
player.keyReleased(e);
}
#Override
public void keyPressed(KeyEvent e) {
player.keyPressed(e);
}
}// end class TAdapter
}// end class Game
Whenever I'm trying to use the up and left controls while firing (space bar), or down and right while firing, the game is unable to detect the pressing of the space bar.
KeyEvents are only generated for the last key pressed. If you want to handle multiple keys being pressed at the same time then you need to:
keep track of a key that has been pressed/released
use a Swing Timer to schedule the animation.
Then whenever the timer fires you check which keys are currently pressed and the do the action for that key.
Hi I am trying to make a red box appear at the bottom of a JPanel .I wish for this box to move to one corner of the screen and stop and then start moving the other way,however i have been unable make the box stop the following is the code i have been working with
import java.awt.*;
import java.awt.event.*;
import javax.swing.*;
import javax.swing.Timer;
public class JavaApplication13 extends JPanel {
public static void main(String[] args) {
JFrame rough = new JFrame("Panamr");
rough.setVisible(true);
rough.setLocation(1, 1);
rough.setSize(500, 500);
rough.setContentPane(mamals);
}
public static int iomega(int x, int y) {
if (y == 1) {
diget = -5;
time.stop();
}
if (y == 0) {
diget = 5;
}
return diget;
}
static JavaApplication13 mamals = new JavaApplication13();
JavaApplication13() {
setBackground(Color.red);
}
static int oy = 400;
static int ox = 200;
static int diget;
static Timer time = new Timer(100, new ActionListener() {
public int xy = 1;
#Override
public void actionPerformed(ActionEvent e) {
iomega(ox, xy);
if (ox == 500) {
xy = 1;
}
if (ox == 0) {
xy = 0;
}
ox = ox - iomega(ox, oy);
/*if(ox!=500){
ox=ox-diget;
if(ox==0){
diget=-5;}
else {
diget=5;
}
}*/
}
});
boolean test = true;
public void paint(Graphics g) {
super.paint(g);
g.setColor(Color.black);
g.fillRect(ox, oy, 60, 60);
time.start();
repaint();
}
}
your co-ordiantes for the frames/panels size is off, you should calculate this dynamically maybe, or have a final value. Next your xy=0 and xy=1 should be swapped like this:
if (ox == 400) {//this was a larger number then the panel/frame so it went offscreen
xy = 0;//swapped
}
if (ox == 0) {
xy = 1;//swapped
}
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.