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POJava applet can't find resources in jar if run locally
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  1. POJava applet can't find resources in jar if run locally
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    copied!<p>Problem: Java applet can't load resources located inside its jar when run locally on windows platforms. The same applet can load the resources if it is launched from a web server instead of launched locally or if it's launched locally on a linux system. In all cases the applet is launched using an applet tag.</p> <p>Steps to reproduce</p> <p>1) Build applet class code below and create a jar containing the following:</p> <blockquote> <ul> <li>TestApplet.class</li> <li>iconimg.png</li> <li>test.html</li> <li>META-INF folder (standard manifest with one line: "Manifest-Version: 1.0")</li> </ul> </blockquote> <p>Here's a link to the image png file I used: <a href="http://flexibleretirementplanner.com/java/java-test/iconimg.png" rel="nofollow">http://flexibleretirementplanner.com/java/java-test/iconimg.png</a></p> <p>The file test.html has one line:</p> <blockquote> <pre><code>&lt;h1&gt;Text from test.html file&lt;/h1&gt; </code></pre> </blockquote> <p>2) create launch.html in same folder as test.jar as follows:</p> <pre><code>&lt;html&gt;&lt;center&gt;&lt;title&gt;Test Applet&lt;/title&gt;&lt;applet archive = "test.jar" code = "TestApplet.class" name = "Test Applet" width = "250" height = "150" hspace = "0" vspace = "0" align = "middle" mayscript = "true" &gt;&lt;/applet&gt;&lt;/center&gt;&lt;/html&gt; </code></pre> <p>3) With test.jar in the same local folder as launch.html, click on launch.html</p> <p>4) Notice that getResource() calls for imgicon.png and test.html both return null.</p> <p>5) Upload launch.html and test.jar to a web server and load launch.html and notice that the resources are found.</p> <p>TestApplet.java</p> <pre><code>import java.applet.AppletContext; import java.io.IOException; import java.net.URL; import javax.swing.ImageIcon; import javax.swing.JApplet; import javax.swing.JEditorPane; import javax.swing.JLabel; import javax.swing.JPanel; public class TestApplet extends JApplet { public TestApplet() { try { jbInit(); } catch (Exception ex) { ex.printStackTrace(); } } public void init() { JPanel topPanel = new JPanel(); JLabel iconLabel; URL url = TestApplet.class.getClassLoader().getResource("iconimg.png"); if (url != null) iconLabel = new JLabel(new ImageIcon(url)); else iconLabel = new JLabel("getResource(iconimg.png)==null"); topPanel.add(iconLabel); URL url2; url2 = TestApplet.class.getClassLoader().getResource("test.html"); if (url2 == null) { JLabel errorLabel = new JLabel("getResource(test.html) == null"); topPanel.add(errorLabel); } else { try { JEditorPane htmlPane = new JEditorPane(url2); topPanel.add(htmlPane); } catch (IOException ioe) { System.err.println("Error displaying " + url2); } } getContentPane().add(topPanel); } private void jbInit() throws Exception { } } </code></pre>
 

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