title: Null Pointer Exception on getGraphics()
body: <p>my application looks like that, i am getting a null pointer exception at the draw() method, to be exact at g.drawImage(img, 0, 0, null)</p>
  
  <pre><code>package com.ochs.game;
  
  import java.awt.Dimension;
  import java.awt.Graphics;
  import java.awt.Graphics2D;
  import java.awt.image.BufferedImage;
  
  import javax.swing.JFrame;
  import javax.swing.JPanel;
  
  public class Game extends JPanel implements Runnable{
  private static final long serialVersionUID = 8229934361462702491L;
  
  public static final int WIDTH = 320;
  public static final int HEIGHT = 240;
  public static final int SCALE = 2;
  
  public boolean isRunning;
  
  private BufferedImage img;
  private Graphics2D g2d;
  
  public Game() {
      setFocusable(true);
      requestFocus();
      start();
  }
  
  public void start() {
      isRunning = true;
      new Thread(this).start();
  }
  
  public void stop() {
      isRunning = false;
  }
  
  public void run() {
      long start;
      init();
      while(isRunning) {
          start = System.currentTimeMillis();
  
          update();
          render();
          draw();
  
          try {
              Thread.sleep(5 - (System.currentTimeMillis() - start));
          } catch (Exception e) {
          }
      }
  }
  
  public void init() {
      img = new BufferedImage(WIDTH*SCALE, HEIGHT*SCALE, BufferedImage.TYPE_INT_RGB);
      g2d = (Graphics2D) img.getGraphics();
  }
  
  public void update() {
  
  }
  
  public void render() {
  
  }
  
  public void draw() {
      Graphics g = getGraphics();
      g.drawImage(img, 0, 0, null);    // &lt;&lt;&lt;&lt;&lt; getting null pointer here!
  }
  
  public static void main(String[] args) {
      Dimension size = new Dimension(WIDTH*SCALE, HEIGHT*SCALE);
      Game gameComponent = new Game();
      JFrame frame = new JFrame();
      frame.setVisible(true);
      frame.setSize(size);
      frame.setLocationRelativeTo(null);
      frame.setResizable(false);
      frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
      frame.add(gameComponent);
  }
  }
  </code></pre>
  
  <p>Now my question is: why do i get a null pointer exception when trying to draw the bufferedimage called img? I also tried just outputting some string by using drawString() but this just gives myself a nullpointerexception, too.
  does anyone has an advice? </p>