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PONull pointer exception despite done right
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  1. PONull pointer exception despite done right
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    copied!<p>I recently was coding but encountered an null pointer exception the stack trace says </p> <pre><code>Exception in thread "main" java.lang.NullPointerException at com.masterkgames.twisteddream.level.SpawnLevel.generateLevel(SpawnLevel.java:34) at com.masterkgames.twisteddream.level.Level.&lt;init&gt;(Level.java:22) at com.masterkgames.twisteddream.level.SpawnLevel.&lt;init&gt;(SpawnLevel.java:16) at com.masterkgames.twisteddream.Game.&lt;init&gt;(Game.java:49) at com.masterkgames.twisteddream.Game.main(Game.java:138) </code></pre> <p>below are the 3 mentioned classes</p> <p>Spawnlevel.java: package com.masterkgames.twisteddream.level;</p> <pre><code>import java.awt.image.BufferedImage; import java.io.IOException; import javax.imageio.ImageIO; import com.masterkgames.twisteddream.level.tile.Tile; public class SpawnLevel extends Level { private Tile[] tiles; private int[] levelPixels; public SpawnLevel(String path) { super(path); } protected void loadLevel(String path){ try{ BufferedImage image = ImageIO.read(SpawnLevel.class.getResource(path)); int w = image.getWidth(); int h = image.getHeight(); tiles = new Tile[w * h]; levelPixels = new int[w * h]; image.getRGB(0,0,w,h,levelPixels,0,w); }catch(IOException e){ e.printStackTrace(); } } protected void generateLevel(){ for(int i = 0; i &lt; levelPixels.length; i++){ if(levelPixels[i] == 0xff00) tiles[i] = Tile.Grass; if(levelPixels[i] == 0xffff00) tiles[i] = Tile.Rose; if(levelPixels[i] == 0x7f7f00) tiles[i] = Tile.Stone; } } } </code></pre> <p>level.java:</p> <pre><code>package com.masterkgames.twisteddream.level; import com.masterkgames.twisteddream.graphics.Screen; import com.masterkgames.twisteddream.level.tile.Tile; public class Level { public Screen screen; protected int width, height; protected Tile[] tiles; protected int[] tilesInt; public Level(int width, int height) { this.width = width; this.height = height; tilesInt = new int[width * height]; generateLevel(); } public Level(String path) { loadLevel(path); generateLevel(); } protected void generateLevel() { } private void loadLevel(String path) { } public void update() { } private void time() { } public void render(int xScroll, int yScroll, Screen screen) { screen.setOffset(xScroll, yScroll); int x0 = xScroll &gt;&gt; 4; int x1 = (xScroll + screen.width + 16) &gt;&gt; 4; int y0 = yScroll &gt;&gt; 4; int y1 = (yScroll + screen.height + 16) &gt;&gt; 4; for (int y = y0; y &lt; y1; y++) { for (int x = x0; x &lt; x1; x++) { // getTile(x, y).render(x, y, screen); if (x + y * 16 &lt; 0 || x + y * 16 &gt;= 256) { Tile.Void.render(x, y, screen); continue; } tiles[x + y * 16].render(x, y, screen); } } } public Tile getTile(int x, int y) { if (x &lt; 0 || y &lt; 0) return Tile.Void; if (x &gt;= width || y &gt;= height) return Tile.Void; if (tilesInt[x + y * width] == 0) return Tile.Grass; if (tilesInt[x + y * width] == 1) return Tile.Rose; if (tilesInt[x + y * width] == 2) return Tile.Stone; return Tile.Void; } } </code></pre> <p>and lastly game.java:</p> <pre><code>package com.masterkgames.twisteddream; import java.awt.Canvas; import java.awt.Color; import java.awt.Dimension; import java.awt.Font; import java.awt.Graphics; import java.awt.image.BufferStrategy; import java.awt.image.BufferedImage; import java.awt.image.DataBufferInt; import javax.swing.JFrame; import com.masterkgames.twisteddream.entity.mob.Player; import com.masterkgames.twisteddream.graphics.Screen; import com.masterkgames.twisteddream.input.Keyboard; import com.masterkgames.twisteddream.level.Level; import com.masterkgames.twisteddream.level.SpawnLevel; public class Game extends Canvas implements Runnable { private static final long serialVersionUID = 1L; public static int width = 300; public static int height = 168; public static int scale = 3; public String Title = "Twisted Dream"; private Thread thread; private boolean running = false; private Screen screen; private Keyboard key; private Level level; private Player player; private JFrame frame; private BufferedImage image = new BufferedImage(width, height, BufferedImage.TYPE_INT_RGB); private int[] pixels = ((DataBufferInt)image.getRaster().getDataBuffer()).getData(); public Game() { Dimension size = new Dimension(width * scale, height * scale); setPreferredSize(size); screen = new Screen(width,height); key = new Keyboard(); level = new SpawnLevel("/textures/level.png"); player = new Player(key); frame = new JFrame(); addKeyListener(key); } public synchronized void start() { thread = new Thread(this, "Display"); thread.start(); running = true; } public synchronized void stop() { running = false; try { thread.join(); } catch (InterruptedException e) { e.printStackTrace(); } } 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 updates = 0; requestFocus(); while (running) { long nowTime = System.nanoTime(); delta += (nowTime - lastTime) / ns; lastTime = nowTime; while (delta &gt;= 1){ update(); updates++; delta--; } render(); frames++; if(System.currentTimeMillis() - timer &gt; 1000){ timer += 1000; System.out.println(updates + " ups, " + frames + " fps"); frame.setTitle(Title + " | " + updates + " ups, " + frames + " fps"); updates = 0; frames = 0; } } stop(); } public void update() { key.update(); player.update(); } public void render() { BufferStrategy bs = getBufferStrategy(); if (bs == null) { createBufferStrategy(3); return; } screen.clear(); int xScroll = player.x - screen.width / 2; int yScroll = player.y - screen.height / 2; level.render(xScroll, yScroll, screen); player.render(screen); for(int i = 0; i &lt; pixels.length; i++){ pixels[i] = screen.pixels[i]; } Graphics g = bs.getDrawGraphics(); g.drawImage(image,0,0,getWidth(),getHeight(),null); g.setFont(new Font("arial", 0, 15)); g.setColor(Color.white); g.dispose(); bs.show(); } public static void main(String[] args) { Game game = new Game(); game.frame.setResizable(false); game.frame.setTitle(game.Title); game.frame.add(game); game.frame.pack(); game.frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE); game.frame.setLocationRelativeTo(null); game.frame.setVisible(true); game.start(); } } </code></pre> <p>p.s this issue according to the stack trace is in the line for(int i = 0; i &lt; levelPixels.length; i++) in SpawnLevel.java</p>
 

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