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POObject array - Null Pointer Exception
 

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    <p>I want to create 2D array of objects, but i get null pointer exception no matter how I create it. How should I make array of objects to get them work? Here is my code: </p> <p>Game.java package com.jakob.game1;</p> <pre><code>import java.awt.BorderLayout; import java.awt.Color; import java.awt.Graphics; import java.awt.Image; import java.awt.Canvas; import java.awt.event.MouseEvent; import java.awt.event.MouseMotionListener; import java.awt.image.BufferStrategy; import java.util.Random; import javax.swing.JFrame; public class Game extends Canvas implements Runnable, MouseMotionListener{ private static final long serialVersionUID = 1L; public static final int gHeigh = 500; public static final int gWidth = 500; public static final int tHeigh = gHeigh/5; public static final int tWidth = gWidth/5; private boolean running; public Random random; public BufferStrategy b; public Graphics g; public Image bi; public Pixel[][] pixel = new Pixel[tHeigh][tWidth]; private void start(){ running = true; new Thread(this).start(); } public static void main(String args[]){ Game game = new Game(); JFrame frame = new JFrame("Game test"); frame.setLayout(new BorderLayout()); frame.setBounds(0, 0, gHeigh, gWidth); frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE); frame.add(game, BorderLayout.CENTER); //frame.pack(); frame.setResizable(false); frame.setLocationRelativeTo(null); frame.setVisible(true); game.start(); } public void run() { bi = createImage(gHeigh, gWidth); g = bi.getGraphics(); g.setColor( Color.black ); g.fillRect( 0, 0, gHeigh, gWidth); g.setColor( Color.white ); addMouseMotionListener( this ); for(int i=0; i&lt;tHeigh; i++){ for(int j=0; j&lt;tWidth; j++){ if(pixel == null){ pixel[i][j] = new Pixel; //No matter what I write here it can't create this } } } if(pixel != null){ for(int i=0; i&lt;tHeigh; i++){ for(int j=0; j&lt;tWidth; j++){ pixel[i][j].setColor(new Color(random.nextInt(256), random.nextInt(256), random.nextInt(256))); } } } while(running){ for(int i=0; i&lt;tHeigh ;i++){ for(int j=0; j&lt;tWidth; j++){ paint(g, i*5, j*5); } } } } public void paint(Graphics g, int x, int y){ g.setColor(pixel[x][y].getColor()); g.fillRect(x, y, 5, 5); } public void mouseDragged(MouseEvent e) { g.fillRect(e.getX()-2, e.getY()-2, 4, 4); repaint(); e.consume(); } public void mouseMoved(MouseEvent e) { } public void update( Graphics g ) { g.drawImage( bi, 0, 0, this ); } public void paint( Graphics g ) { update( g ); } } </code></pre> <p>Pixel.java</p> <pre><code>package com.jakob.game1; import java.awt.Color; public class Pixel { private Color color; public Pixel(){ color = new Color( 0,0,0); } public void setColor(Color color){ this.color = color; } public Color getColor(){ return this.color; } } </code></pre>
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      1. USBalaswamy Vaddeman
 

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