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Bricks array not forming

I'm having troubles with my Brick Breaker game that I am making in my 12th grade programming class.
Currently, it seems that only the brick in Bricks.render does draw. When I output what the X and Y of the bricks should be it puts each brick in the right position. So I believe I'm drawing it wrong.
MCVE:
Game.java
package main;
import java.awt.Canvas;
import java.awt.Color;
import java.awt.FontMetrics;
import java.awt.Graphics;
import java.awt.Graphics2D;
import java.awt.RenderingHints;
import java.awt.image.BufferStrategy;
public class Game extends Canvas implements Runnable {
// variables
private static final long serialVersionUID = 1L;
public static final int WIDTH = 480, HEIGHT = 600, SCALE = 1;
public final String TITLE = "Brick Breaker";
private static boolean running = false;
private Thread thread;
private int fpsDisplay = 0;
Bricks[] level1 = new Bricks[16];
// creates a new Game (which creates the game window)
public static void main(String[] args) {
new Game();
}
public Game() {
new GameWindow(WIDTH, HEIGHT, SCALE, TITLE, this);
System.out.println("[" + TITLE + " has started.]");
}
// called in GameWindow, starts the thread and game loop
public synchronized void start() {
if (running)
return;
thread = new Thread(this);
thread.start();
running = true;
}
public void init() {
this.createlevel1();
}
// used for updating what's happening in the game
private void tick() {
}
// renders the graphics
private void render() {
// --------- INIT GRAPHICS --------- //
BufferStrategy bs = this.getBufferStrategy();
if (bs == null) {
this.createBufferStrategy(3);
return;
}
Graphics g = bs.getDrawGraphics();
Graphics2D g2d = (Graphics2D) g;
((Graphics2D) g).setRenderingHint(RenderingHints.KEY_ANTIALIASING, RenderingHints.VALUE_ANTIALIAS_ON);
FontMetrics fontMetrics = g2d.getFontMetrics();
// --------- INIT GRAPHICS --------- //
// clearing background
super.paint(g);
g2d.setColor(Color.black);
g2d.drawString(Integer.toString(fpsDisplay) + " FPS",
WIDTH - 9 - fontMetrics.stringWidth(Integer.toString(fpsDisplay) + " FPS"), 14);
// render level 1
for (int i = 0; i < 16; i++) {
level1[i].render(g);
}
// render level 1
// ---------
g.dispose();
g2d.dispose();
bs.show();
// ---------
}
public void createlevel1() {
int brickCount = 0;
for (int i = 0; i < 4; i++) {
for (int j = 0; j < 4; j++) {
level1[brickCount] = new Bricks(50 + i * 100, 50 + j * 100);
System.out.println("X: " + (50 + i * 100) + " Y: " + (50 + j * 100));
brickCount++;
}
}
}
// 60 tps game loop
public void run() {
init();
long lastTime = System.nanoTime();
final double amountOfTicks = 60.0;
double ns = 1000000000 / amountOfTicks;
double delta = 0;
int updates = 0;
int frames = 0;
long timer = System.currentTimeMillis();
while (running) {
long now = System.nanoTime();
delta += (now - lastTime) / ns;
lastTime = now;
if (delta >= 1) {
tick();
updates++;
delta--;
}
render();
frames++;
if (System.currentTimeMillis() - timer > 1000) {
timer += 1000;
System.out.println("Ticks: " + updates + ", FPS: " + frames);
fpsDisplay = frames;
updates = 0;
frames = 0;
}
}
stop();
}
// called at the end of the loop, stops the thread
public synchronized void stop() {
try {
thread.join();
running = false;
} catch (InterruptedException e) {
e.printStackTrace();
}
}
}
Bricks.java
package main;
import java.awt.Color;
import java.awt.Graphics;
import java.awt.Graphics2D;
#SuppressWarnings("unused")
public class Bricks {
private int x, y, w, h;
private Boolean isAlive;
private Color randColour;
public Bricks(int x, int y) {
x = this.x;
y = this.y;
w = 75;
h = 25;
isAlive = true;
randColour = Color.blue;
}
public void render(Graphics g) {
g.setColor(randColour);
g.fillRect(x, y, w, h);
}
}
GameWindow.java
package main;
import java.awt.Canvas;
import java.awt.Dimension;
import java.io.File;
import java.io.IOException;
import javax.imageio.ImageIO;
import javax.swing.JFrame;
public class GameWindow extends Canvas {
private static final long serialVersionUID = -5131420759044457697L;
public GameWindow(int WIDTH, int HEIGHT, int SCALE, String TITLE, Game game) {
JFrame frame = new JFrame(TITLE);
frame.setPreferredSize(new Dimension(WIDTH * SCALE, HEIGHT * SCALE));
frame.setMaximumSize(new Dimension(WIDTH * SCALE, HEIGHT * SCALE));
frame.setMinimumSize(new Dimension(WIDTH * SCALE, HEIGHT * SCALE));
try {
frame.setIconImage(ImageIO.read(new File("res/Brick-icon.png")));
} catch (IOException e) {
frame.setIconImage(null);
e.printStackTrace();
System.out.println("ICON ERROR: Icon image not found. (Default Icon is set.)");
}
frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
frame.setResizable(false);
frame.setLocationRelativeTo(null);
frame.add(game);
frame.pack();
game.start();
// displays the window 400ms later to allow for the game to fully load
try {
Thread.sleep(400);
} catch (InterruptedException e) {
// TODO Auto-generated catch block
e.printStackTrace();
}
frame.setVisible(true);
}
}

In Bricks.java:
x = this.x;
y = this.y;
should be:
this.x = x;
this.y = y;

Canvas doesn't update after drawing images

I am designing a game in Java. I'm using a bit of code I found at java-gaming.org, and it seems to be working strangely.
When I run the loop as given, it will update my canvas correctly. However, I don't want it to always be updating my "background" so to speak. To fix this I had it only run once. Now it appears to run, but does not display the image I painted.
I've uploaded screenshots of the program running once (broken) and the program running continuously (working). See them on imgur.
tldr; Everything appears to run, but it doesn't display anything in my frame. see code below.
package main;
//imports...
import java.awt.Canvas;
import java.awt.Dimension;
import java.awt.Graphics2D;
import java.awt.event.KeyListener;
import java.awt.image.BufferStrategy;
import java.awt.image.BufferedImage;
import java.io.File;
import java.io.IOException;
import javax.imageio.ImageIO;
import javax.swing.JFrame;
import javax.swing.JPanel;
public class GameEngine implements Runnable {
//declare variables...
final static int B_HEIGHT = 20;
final static int B_WIDTH = 20;
private int cellWidth = GameTester.WIDTH / B_WIDTH;
private int cellHeight = GameTester.HEIGHT / B_HEIGHT;
protected boolean init = true;
JFrame frame;
Canvas canvas;
BufferStrategy bufferStrategy;
Board gameBoard;
Generator gen;
long desiredFPS = 60;
long desiredDeltaLoop = (1000 * 1000 * 1000) / desiredFPS;
boolean running = true;
public GameEngine(int width, int height) {
//create the gamespace...
gameBoard = new Board(B_WIDTH, B_HEIGHT);
gen = new Generator();
gen.addWalls(gameBoard);
agents.Champion champ = new agents.Champion();
items.Item item = new items.Item();
gameBoard.placeChampion(champ);
gameBoard.placeItem(item);
//frame magic...
frame = new JFrame("Basic Game");
JPanel panel = (JPanel) frame.getContentPane();
panel.setPreferredSize(new Dimension(width, height));
panel.setLayout(null);
canvas = new Canvas();
canvas.setBounds(0, 0, width, height);
canvas.setIgnoreRepaint(true);
panel.add(canvas);
frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
frame.pack();
frame.setResizable(false);
frame.setVisible(true);
canvas.createBufferStrategy(2);
bufferStrategy = canvas.getBufferStrategy();
canvas.requestFocus();
}
//actual game mechanics...
public void run() {
long beginLoopTime;
long endLoopTime;
long currentUpdateTime = System.nanoTime();
long lastUpdateTime;
long deltaLoop;
//game loop...
while (running) {
beginLoopTime = System.nanoTime();
//this draws things
render();
lastUpdateTime = currentUpdateTime;
currentUpdateTime = System.nanoTime();
//update magic...
update((int) ((currentUpdateTime - lastUpdateTime) / (1000 * 1000)));
endLoopTime = System.nanoTime();
deltaLoop = endLoopTime - beginLoopTime;
if (deltaLoop <= desiredDeltaLoop) {
try {
Thread.sleep((desiredDeltaLoop - deltaLoop) / (1000 * 1000));
} catch (InterruptedException e) {
// Do nothing
}
}
}
}
//creates g object...
private void render() {
Graphics2D g = (Graphics2D) bufferStrategy.getDrawGraphics();
g.clearRect(0, 0, GameTester.WIDTH, GameTester.HEIGHT);
render(g);
g.dispose();
bufferStrategy.show();
}
// does nothing important...
private double x = 0;
protected void update(int deltaTime) {
if (GameTester.dbglvl > 1) {
System.out.println("update called");
}
x += deltaTime * 0.2;
while (x > 500) {
x -= 500;
}
}
// ACTUAL GAME DRAWING MECHANISM...
protected void render(Graphics2D g) {
//first run
if (init) {
renderinit(g);
} else {
//every other time after first run
}
}
//first run (generates game board)
protected void renderinit(Graphics2D g) {
BufferedImage img = null;
//loop through 2d array
for (int row = 0; row < gameBoard.getWidth(); row++) {
for (int col = 0; col < gameBoard.getHeight(); col++) {
//get image path
String str = gameBoard.getSpace(row, col).getPath();
//debug info
if (GameTester.dbglvl > 1) {
System.out.println(gameBoard.getSpace(row, col).getPath());
}
//get the image to be rendered
try {
img = ImageIO.read(new File(str));
} catch (IOException e) {
if (GameTester.dbglvl > 0) {
System.out
.println("image get failed - image specified: "
+ str + " ");
}
}
if (GameTester.dbglvl > 1) {
System.out.println("Image Destination: (" + row * cellWidth
+ ", " + col * cellHeight + ")");
}
//draws given image
g.drawImage(img, row * cellWidth, // DX1
col * cellHeight, // DY1
(row * cellWidth) + cellWidth, // DX2
(col * cellHeight) + cellHeight, // DY2
0, // SX1
0, // SY1
img.getWidth(), // SX2
img.getHeight(), // SY2
null);
}
}
//done with first time run
init = false;
if (GameTester.dbglvl > 0) {
System.out.println("Board Rendered");
}
}
}

(Java) Getting error with 2D Game

I'm having an issue with my 2D game that I am following a tutorial for. I've scanned my code several times and cannot seem to resolve it. Sorry if my question sounds stupid, but I do welcome any help whatsoever.
Here's my source:
package game;
import gfx.SpriteSheet;
import java.awt.BorderLayout;
import java.awt.Canvas;
import java.awt.Color;
import java.awt.Dimension;
import java.awt.Graphics;
import java.awt.image.BufferStrategy;
import java.awt.image.BufferedImage;
import java.awt.image.DataBufferInt;
import javax.swing.JFrame;
public class Game extends Canvas implements Runnable
{
private static final long serialVersionUD = 1L;
public static final int WIDTH = 160;
public static final int HEIGHT = WIDTH/12*9;
public static final int SCALE = 3;
public static final String NAME = "Game";
private JFrame frame;
public boolean running = false;
public int tickCount = 0;
private BufferedImage image = new BufferedImage(WIDTH, HEIGHT, BufferedImage.TYPE_INT_RGB);
private int[] pixels = ((DataBufferInt) image.getRaster().getDataBuffer()).getData();
private SpriteSheet spriteSheet = new SpriteSheet("SpriteSheet.png");
public Game()
{
setMinimumSize(new Dimension(WIDTH * SCALE, HEIGHT * SCALE));
setMaximumSize(new Dimension(WIDTH * SCALE, HEIGHT * SCALE));
setPreferredSize(new Dimension(WIDTH * SCALE, HEIGHT * SCALE));
frame = new JFrame(NAME);
frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
frame.setLayout(new BorderLayout());
frame.add(this, BorderLayout.CENTER);
frame.pack();
frame.setResizable(false);
frame.setLocationRelativeTo(null);
frame.setVisible(true);
}
private synchronized void start()
{
running = true;
new Thread(this).start();
}
private synchronized void stop()
{
running = false;
}
public void run()
{
long lastTime = System.nanoTime();
double nsPerTick = 1000000000D / 60D;
int ticks = 0;
int frames = 0;
long lastTimer = System.currentTimeMillis();
double delta = 0;
while(running)
{
long now = System.nanoTime();
delta += (now - lastTime) / nsPerTick;
lastTime = now;
boolean shouldRender = false;
while(delta >= 1)
{
ticks++;
tick();
delta -= 1;
shouldRender = true;
}
try {
Thread.sleep(2);
} catch (InterruptedException ex) {
}
if(shouldRender)
{
frames++;
render();
}
if(System.currentTimeMillis() - lastTimer >= 1000)
{
lastTimer += 1000;
System.out.println(frames + ", " + ticks);
frames = 0;
ticks = 0;
}
}
}
//Updates all of internal variables and logic and stuff.
public void tick()
{
tickCount++;
for(int i = 0; i < pixels.length; i++)
{
pixels [i] = i + tickCount;
}
}
//prints the updated logic.
public void render()
{
BufferStrategy bs = getBufferStrategy();
if(bs == null)
{
createBufferStrategy(3);
return;
}
Graphics g = bs.getDrawGraphics();
g.setColor(Color.BLACK);
g.fillRect(0, 0, getWidth(), getHeight());
g.drawImage(image, 0, 0, getWidth(), getHeight(), null);
g.dispose();
bs.show();
}
//Main method
public static void main(String[]args)
{
new Game().start();
}
}
package gfx;
import java.awt.image.BufferedImage;
import java.io.IOException;
import javax.imageio.ImageIO;
public class SpriteSheet
{
public String path;
public int width;
public int height;
public int[] pixels;
public SpriteSheet(String path)
{
BufferedImage image = null;
try
{
image = ImageIO.read(SpriteSheet.class.getResourceAsStream(path));
} catch (IOException e)
{
e.printStackTrace();
}
if(image == null)
{
return;
}
this.path = path;
this.width = image.getWidth();
this.height = image.getHeight();
pixels = image.getRGB(0, 0, width, height, null, 0, width);
for(int i = 0; i < pixels.length; i++)
{
pixels[i] = (pixels[i] & 0xff / 64);
}
for(int i = 0; i < 8; i++)
{
System.out.println(pixels[i]);
}
}
}
And here's a link to my video tutorial I'm using: Tutorial
I'm using eclipse on a 64 bit operating system(Windows).
Again, any help would be greatly appreciated, and thank you.
EDIT:
Error message:
Exception in thread "main" java.lang.IllegalArgumentException: input == null!
at javax.imageio.ImageIO.read(ImageIO.java:1348)
at gfx.SpriteSheet.<init>(SpriteSheet.java:21)
at game.Game.<init>(Game.java:34)
at game.Game.main(Game.java:144)
Sorry, forgot error message. XD

The error message is telling you what's wrong: Your image path is wrong. The image path must be given relative to the class files location.

Java - Eclipse IDE, program terminated by a pointer exception error

i was making a program, game in specific, so i started with basic things, but when i try to test it it drops out weird errors which doesn't appear in code, so i suppose my code is fine, but i don't know what could be causing this. :(
This is the error:
Exception in thread "main" java.lang.NullPointerException
at java.awt.image.BufferedImage.<init>(Unknown Source)
at ca.hawk.game.Game.<init>(Game.java:33)
at ca.hawk.game.Game.main(Game.java:126)
And here's the code (package):
package ca.hawk.game;
import java.awt.BorderLayout;
import java.awt.Canvas;
import java.awt.Color;
import java.awt.Dimension;
import java.awt.Graphics;
import java.awt.image.BufferStrategy;
import java.awt.image.BufferedImage;
import java.awt.image.DataBufferInt;
import java.awt.image.IndexColorModel;
import javax.swing.JFrame;
public class Game extends Canvas implements Runnable{
private static final long serialVersionUID = 1L;
public static final int WIDTH = 160;
public static final int HEIGHT = WIDTH / 12 * 9;
public static final int SCALE = 3;
public static final String NAME = "Game";
private static final int BufferedImage = 0;
private static final IndexColorModel TYPE_INT_RGB = null;
private JFrame frame;
public boolean running = false;
public int tickCount = 0;
private BufferedImage image = new BufferedImage(WIDTH, HEIGHT, BufferedImage, TYPE_INT_RGB);
private int[] pixels = ((DataBufferInt) image.getRaster().getDataBuffer()).getData();
public Game(){
setMinimumSize(new Dimension(WIDTH * SCALE, HEIGHT * SCALE));
setMaximumSize(new Dimension(WIDTH * SCALE, HEIGHT * SCALE));
setPreferredSize(new Dimension(WIDTH * SCALE, HEIGHT * SCALE));
frame = new JFrame(NAME);
frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
frame.setLayout(new BorderLayout());
frame.add(this, BorderLayout.CENTER);
frame.pack();
frame.setResizable(false);
frame.setLocationRelativeTo(null);
frame.setVisible(true);
}
public synchronized void start() {
running = true;
new Thread(this).start();
}
private synchronized void stop(){
running = false;
}
public void run() {
long lastTime = System.nanoTime();
double nsPerTick = 1000000000D/60D;
int ticks = 0;
int frames = 0;
long lastTimer = System.currentTimeMillis();
double delta = 0;
while (running){
long now = System.nanoTime();
delta += (now - lastTime) / nsPerTick;
lastTime = now;
boolean shouldRender = true;
while (delta >= 1){
ticks++;
tick();
delta -= 1;
shouldRender = true;
}
try {
Thread.sleep(2);
} catch (InterruptedException e) {
e.printStackTrace();
}
if (shouldRender){
frames++;
render();
}
if (System.currentTimeMillis() - lastTimer > 1000){
lastTimer += 1000;
System.out.println(frames +", "+ ticks);
frames = 0;
ticks = 0;
}
}
}
public void tick(){
tickCount++;
}
public void render(){
BufferStrategy bs = getBufferStrategy();
if (bs == null){
createBufferStrategy(3);
return;
}
Graphics g = bs.getDrawGraphics();
g.setColor(Color.BLACK);
g.fillRect(0, 0, getWidth(), getHeight());
g.drawImage(image, 0, 0, getWidth(), getHeight(), null);
g.dispose();
bs.show();
}
public static void main(String[] args){
new Game().start();
}
}

change :
private BufferedImage image = new BufferedImage(WIDTH, HEIGHT, BufferedImage, TYPE_INT_RGB);
to:
private BufferedImage image = new BufferedImage(WIDTH, HEIGHT, BufferedImage, BufferedImage.TYPE_INT_ARGB);
you set a varialbe TYPE_INT_RGB that is null, so when you make a buffered image it throws null pointer exception.
TYPE_INT_RGB is a public static final variable on BufferedImage. Public means you can access it in your object, static means its a class variable not an object variable and final means its ts always the same value e.g if its 10 it will always be 10.
with BufferedImage.TYPE_INT_RGB you can access it.

Variable stops being set after "if" statement is added [closed]

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Closed 9 years ago.
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I have a input class. When up is pressed it sets player.hasJumped = true; and when hasJumped is true, it changes dy to -3 in the player class. The problem is, that hasJumped is being set to true, but the variable is not changing. I can't really figure out why this is happening. This is a short sample of my code, I can provide more if needed.
InputHandler.java
import java.awt.event.KeyEvent;
import java.awt.event.KeyListener;
public class InputHandler implements KeyListener{
Player player = new Player();
private boolean[] keys = new boolean[120];
public boolean up;
public void tick(){
up = keys[KeyEvent.VK_UP] || keys[KeyEvent.VK_W];
if(player.jumpReady){
if(up){
player.inAir = true;
System.out.println("JUMPED " + player.inAir);
}
}
}
public void keyPressed(KeyEvent e) {
keys[e.getKeyCode()] = true;
}
public void keyReleased(KeyEvent e) {
keys[e.getKeyCode()] = false;
}
Player.java
import java.awt.Color;
import java.awt.Graphics;
import java.awt.Graphics2D;
import java.awt.Rectangle;
import java.awt.image.BufferedImage;
import java.io.File;
import java.io.IOException;
import javax.imageio.ImageIO;
public class Player {
int x;
int y;
int dx;
public long xElapsed = 0;
public int dy;
int width = 50;
int height = 75;
public int hangTime = 0;
int maxHangTime = 100;
int nextX = 1000;
public int playerSpeed = 7;
public int coinsCollected = 0;
public boolean isMoving = true;
public boolean hasJumped = false;
public boolean jumpReady = true;
public boolean hasCollided = false;
public boolean inAir = false;
private BufferedImage moving1 = null;
private String path1 = "res/player_moving_1.png";
public Player(){
try {
moving1 = ImageIO.read(new File(path1));
}catch (IOException e) {
e.printStackTrace();
System.err.println("Could not load image " + moving1 + " at path" + path1);
}
x = 150;
y = 250;
}
public void render(Graphics g){
Graphics2D g2d = (Graphics2D) g;
g2d.drawImage(moving1, x, y, null);
}
public void move(){
x = x + dx;
y = y + dy;
xElapsed++;
if(xElapsed == nextX){
upSpeed();
nextX += 1000;
}
if(inAir){
System.out.println("test");
dy = -3;
}
}
public void paint(Graphics g){
g.setColor(Color.RED);
g.fillRect(x, y, width, height);
}
public void upSpeed(){
playerSpeed++;
}
public int getX(){
return x;
}
public int getY(){
return y;
}
public long getXElapsed(){
return xElapsed;
}
public double getSpeed(){
return playerSpeed;
}
public int getNextX(){
return nextX;
}
public int getCoinsCollected(){
return coinsCollected;
}
public Rectangle bounds(){
return (new Rectangle(x, y, width, height));
}
}
Game.java
private static final long serialVersionUID = 1L;
public static final int WIDTH = 350;
public static final int HEIGHT = WIDTH / 16 * 9;
public static final int SCALE = 2;
private Thread thread;
private JFrame frame;
private InputHandler input;
private boolean running = false;
private Screen screen;
private BufferedImage image = new BufferedImage(WIDTH, HEIGHT, BufferedImage.TYPE_INT_RGB);
private int[] pixels = ((DataBufferInt)image.getRaster().getDataBuffer()).getData();
Player player = new Player();
public Game() {
Dimension size = new Dimension(WIDTH * SCALE, HEIGHT * SCALE);
setPreferredSize(size);
screen = new Screen(WIDTH, HEIGHT);
frame = new JFrame();
input = new InputHandler();
addKeyListener(input);
setFocusable(true);
}
public void run() {
long lastTime = System.nanoTime();
long timer = System.currentTimeMillis();
final double ns = 1000000000.0 / 60.0;
double delta = 0;
int frames = 0;
int ticks = 0;
while(running){
long now = System.nanoTime();
delta += (now - lastTime) / ns;
lastTime = now;
while(delta >= 1){
tick();
ticks++;
delta--;
}
render();
frames++;
if(System.currentTimeMillis() - timer > 1000){
timer += 1000;
System.out.println(ticks + " tps, " + frames + " fps");
ticks = 0;
frames = 0;
}
}
stop();
}
public void tick(){
input.tick();
player.move();
collision();
obstacleHole.move();
obstacleWolf.move();
coin.move();
}

Within Game.java pass the object player as argument within the constructor of InputHandler as follows:
public Game() {
Dimension size = new Dimension(WIDTH * SCALE, HEIGHT * SCALE);
setPreferredSize(size);
screen = new Screen(WIDTH, HEIGHT);
frame = new JFrame();
input = new InputHandler(player);//pass player object as argument
addKeyListener(input);
setFocusable(true);
}
And change the InputHandler class as follows:
public class InputHandler implements KeyListener{
Player player ; //Don't initialize it.
//Create a parametric constructor
public InputHandler(Player player)
{
this.player = player;
}
//...And then proceed with other stuffs
}