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POWhat is this error trying to tell me in NetBeans?
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  1. POWhat is this error trying to tell me in NetBeans?
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    copied!<p>So I've been working on my program, using GUI for the first time in java. I think I have everything how it supposed to be, but is giving me one error:</p> <pre><code>Exception in thread "main" java.lang.NullPointerException at GUIProgram.&lt;init&gt;(GUIProgram.java:41) at Inventory.main(Inventory.java:12) Java Result: 1 BUILD SUCCESSFUL (total time: 3 seconds) </code></pre> <p>I don't know what exactly I have to do, I keep trying to fix it, but I can't.</p> <p>If you need more information to find out what is wrong, please let me know.</p> <p><strong>Edit</strong> (copied from comment)</p> <pre><code>Product[] array = new Product[table.length]; float total = 0; float fee = 0; for(Product p: array) { total += p.getTotal(); fee += p.getRestockingFee(); } </code></pre> <p>This is the GUIProgram class I am building. </p> <pre><code> import javax.swing.*; import java.awt.*; public class GUIProgram extends JFrame { public GUIProgram() { super("Welcome to the Inventory Program"); setLayout(new FlowLayout()); String[] columnNames = {"Item", "Item No.", "Unit", "Price"}; Product[] table = new Product[5]; table[0] = new Product("chocolate", 1023, 124, 1.50f); table[1] = new Product("ice cream", 1543, 170, 3.35f); table[2] = new Product("milk", 1265, 230, 2.40f); table[3] = new Product("orange juice", 1653, 199, 0.60f); table[4] = new Product("cereal", 1534, 176, 3.50f); for (int i = 0; i &lt; table.length; i++) { JTextField textfield1 = new JTextField(table.length); add(textfield1); float total = 0; float fee = 0; for(Product p: table) { total += p.getTotal(); fee += p.getRestockingFee(); } JTextField textfield2 = new JTextField(table.length); textfield2 = new JTextField(String.format("The total value of the Fruits Inventory is: %.2f", total)); add(textfield2); JTextField textfield3 = new JTextField(table.length); textfield3 = new JTextField(String.format("The total restocking fee is: %.2f", fee)); add(textfield3); } } } </code></pre> <p>I'm just trying to build a GUI for this array.</p>
 

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