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POJLabel won't display image - NullPointerException
 

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  1. POJLabel won't display image - NullPointerException
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    <p>this is my first Java GUI program, and really only my second java program, so take it easy on me :) My program is a result of a lot of googling and reading java docs. My problem is that I have a sprite sheet of 52 cards, and am attempting to save these cards individually to a Buffered Image array using subImage, and just for testing purposes, display all 52 in a window. The File is in the correct directory I made sure of that. I believe that my problem lies with my use of Jlabels, or simply a foolish mistake. Anyways, here is my class that does the sprite sheet splitting </p> <pre><code> package gui; import java.awt.GridLayout; import java.awt.image.BufferedImage; import java.io.File; import javax.imageio.ImageIO; import javax.swing.ImageIcon; import javax.swing.JLabel; import javax.swing.JPanel; public class crdimgs extends JPanel {/** * */ static final long serialVersionUID = 1L; public final int width = 10; public final int height = 20; public int rows = 13; public int cols = 5; public BufferedImage image; File cardimg = new File("Cards.jpg"); BufferedImage cards[]; public void loadsplit(File loadimage){ try{ image = ImageIO.read(loadimage); } catch(Exception error){ System.out.print("error"); } cards = new BufferedImage[cols*rows]; } public crdimgs() { loadsplit(cardimg); setLayout(new GridLayout(rows, cols, 1, 1)); int x = 0; int y = 0; int subimg = 0; for( int i = 0; i &lt; rows; i++) { JPanel panel = new JPanel(); cards[subimg] = new BufferedImage(width, height, 5); cards[subimg] = image.getSubimage(x, y, width, height); panel.add(new JLabel(new ImageIcon(cards[subimg]))); add(panel); x+=width; subimg++; } y+=height; x=0; } } } </code></pre> <p>And my Main class</p> <pre><code>package gui; import javax.swing.JFrame; import java.awt.Color; public class cards extends JFrame { private static final long serialVersionUID = 1L; public cards(){ setTitle("Poker"); setDefaultCloseOperation(EXIT_ON_CLOSE); setSize(1000, 700); setLocationRelativeTo(null); this.getContentPane().setBackground(Color.GREEN); setVisible(true); setResizable(false); add(new crdimgs()); } public static void main(String[] args){ new cards(); } } </code></pre> <p>Errors I receive at the moment are:</p> <pre><code>errorException in thread "main" java.lang.NullPointerException at gui.crdimgs.&lt;init&gt;(crdimgs.java:53) at gui.cards.&lt;init&gt;(cards.java:22) at gui.cards.main(cards.java:28) </code></pre>
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    1. USAndrew Thompson
    1. USTrés DuBiel
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    1. CONote the first line in your `Exception` ... `errorException in thread "main" java.lang.NullPointerException`, it starts with `error`, which is coming from your `ImageIO.read` statement. Something has gone wrong when trying to read the file. Following Hovercraft's advice
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      1. USMadProgrammer
 

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