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    <p>Likely your image is null, possibly because you're looking in the wrong place for it, but to find out, check out which line is 53. </p> <p>Suggestions:</p> <ul> <li>Start <strong>small</strong> and then build on. Don't try to do complex image manipulation until you first successfully read and show a single image.</li> <li>Check where Java is looking for the image, because likely it isn't where you think it is. Put <code>System.out.println(System.getProperty("user.dir"));</code> in your code to find out.</li> <li>Call <code>setVisible(true)</code> <strong>after</strong> adding all components to the JFrame.</li> <li>Improve your exception display code by printing the stack trace: <code>error.printStackTrace()</code> (thanks Mad!).</li> </ul> <p>For example:</p> <pre><code>import java.awt.Color; import java.awt.Component; import java.awt.Dimension; import java.awt.event.MouseAdapter; import java.awt.event.MouseEvent; import java.awt.image.BufferedImage; import java.io.IOException; import java.net.MalformedURLException; import java.net.URL; import java.util.ArrayList; import java.util.Collections; import java.util.List; import javax.imageio.ImageIO; import javax.swing.*; public class PlayingCardTest { public static void main(String[] args) { String pathToDeck = "http://www.jfitz.com/cards/classic-playing-cards.png"; try { final List&lt;ImageIcon&gt; cardImgList = CreateCards.createCardIconList(pathToDeck); SwingUtilities.invokeLater(new Runnable() { public void run() { JFrame frame = new JFrame("Moving Cards"); frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE); frame.add(new CardGameTable(cardImgList, frame)); frame.pack(); frame.setLocationRelativeTo(null); frame.setVisible(true); } }); } catch (MalformedURLException e) { e.printStackTrace(); System.exit(-1); } catch (IOException e) { e.printStackTrace(); System.exit(-1); } } } @SuppressWarnings("serial") class CardGameTable extends JLayeredPane { private static final int PREF_W = 600; private static final int PREF_H = 400; private static final Color BASE_COLOR = new Color(0, 80, 0); private static final int CARD_COUNT = 20; private static final int WIDTH_SHOWING = 20; private JPanel basePane = new JPanel(null); public CardGameTable(List&lt;ImageIcon&gt; cardImgList, final JFrame frame) { basePane.setSize(getPreferredSize()); basePane.setBackground(BASE_COLOR); add(basePane, JLayeredPane.DEFAULT_LAYER); final MyMouseAdapter myMouseAdapter = new MyMouseAdapter(this, basePane); addMouseListener(myMouseAdapter); addMouseMotionListener(myMouseAdapter); for (int i = 0; i &lt; CARD_COUNT; i++) { JLabel card = new JLabel(cardImgList.remove(0)); card.setSize(card.getPreferredSize()); int x = (PREF_W / 2) + WIDTH_SHOWING * (CARD_COUNT - 2 * i) / 2 - card.getPreferredSize().width / 2; int y = PREF_H - card.getPreferredSize().height - WIDTH_SHOWING * 2; card.setLocation(x, y); basePane.add(card); } } @Override public Dimension getPreferredSize() { return new Dimension(PREF_W, PREF_H); } } class MyMouseAdapter extends MouseAdapter { private JLabel selectedCard = null; private JLayeredPane cardGameTable = null; private JPanel basePane = null; private int deltaX = 0; private int deltaY = 0; public MyMouseAdapter(JLayeredPane gameTable, JPanel basePane) { this.cardGameTable = gameTable; this.basePane = basePane; } @Override public void mousePressed(MouseEvent mEvt) { Component comp = basePane.getComponentAt(mEvt.getPoint()); if (comp != null &amp;&amp; comp instanceof JLabel) { selectedCard = (JLabel) comp; basePane.remove(selectedCard); basePane.revalidate(); basePane.repaint(); cardGameTable.add(selectedCard, JLayeredPane.DRAG_LAYER); cardGameTable.revalidate(); cardGameTable.repaint(); deltaX = mEvt.getX() - selectedCard.getX(); deltaY = mEvt.getY() - selectedCard.getY(); } } @Override public void mouseReleased(MouseEvent mEvt) { if (selectedCard != null) { cardGameTable.remove(selectedCard); cardGameTable.revalidate(); cardGameTable.repaint(); basePane.add(selectedCard, 0); basePane.revalidate(); basePane.repaint(); selectedCard = null; } } @Override public void mouseDragged(MouseEvent mEvt) { if (selectedCard != null) { int x = mEvt.getX() - deltaX; int y = mEvt.getY() - deltaY; selectedCard.setLocation(x, y); cardGameTable.revalidate(); cardGameTable.repaint(); } } } class CreateCards { private static final int SUIT_COUNT = 4; private static final int RANK_COUNT = 13; public static List&lt;ImageIcon&gt; createCardIconList(String pathToDeck) throws MalformedURLException, IOException { BufferedImage fullDeckImg = ImageIO.read(new URL(pathToDeck)); int width = fullDeckImg.getWidth(); int height = fullDeckImg.getHeight(); List&lt;ImageIcon&gt; iconList = new ArrayList&lt;ImageIcon&gt;(); for (int suit = 0; suit &lt; SUIT_COUNT; suit++) { for (int rank = 0; rank &lt; RANK_COUNT; rank++) { int x = (rank * width) / RANK_COUNT; int y = (suit * height) / SUIT_COUNT; int w = width / RANK_COUNT; int h = height / SUIT_COUNT; BufferedImage cardImg = fullDeckImg.getSubimage(x, y, w, h); iconList.add(new ImageIcon(cardImg)); } } Collections.shuffle(iconList); return iconList; } } </code></pre> <p>Which shows:<br> <img src="https://i.stack.imgur.com/FKwLY.jpg" alt="enter image description here"></p>
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    1. COAlso, instead of printing `System.out.print("error");` when an exception occurs, use `error.printStackTrace();` and/or re-throw the exception
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    2. CO@MadProgrammer: good point, thanks!
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    3. COIt was your answer that let me see "error" prefixing the output
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