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javajava-web-startjava-websocket

NoClassDefFoundError with Java Web Start and Websockets

My applet works in Eclipse when I run it with "Run As -> Java Applet", but when I try to launch it with a JNLP file, I get a NoClassDefFoundError. Im trying to use the javax.websocket-api inside my application, which uses the tyrus implementation.

Java code: 

import javax.websocket.DeploymentException;
import org.glassfish.tyrus.server.Server;

public class MyApplet extends Applet {
    Server server = new Server("localhost", 8025, "/root/", MyApplet.class);
    try {
        server.start();
    }
    catch (DeploymentException e) {
        e.printStackTrace();
    }
}

Error message:

java.lang.RuntimeException: java.lang.NoClassDefFoundError: javax/websocket/DeploymentException
    at com.sun.deploy.uitoolkit.impl.awt.AWTAppletAdapter.instantiateApplet(Unknown Source)
    at sun.plugin2.applet.Plugin2Manager.initAppletAdapter(Unknown Source)
    at sun.plugin2.applet.Plugin2Manager$AppletExecutionRunnable.run(Unknown Source)
    at java.lang.Thread.run(Unknown Source)
Caused by: java.lang.NoClassDefFoundError: javax/websocket/DeploymentException
    at java.lang.Class.getDeclaredConstructors0(Native Method)
    at java.lang.Class.privateGetDeclaredConstructors(Unknown Source)
    at java.lang.Class.getConstructor0(Unknown Source)
    at java.lang.Class.newInstance(Unknown Source)
    at com.sun.deploy.uitoolkit.impl.awt.AWTAppletAdapter$1.run(Unknown Source)
    at java.awt.event.InvocationEvent.dispatch(Unknown Source)
    at java.awt.EventQueue.dispatchEventImpl(Unknown Source)
    at java.awt.EventQueue.access$500(Unknown Source)
    at java.awt.EventQueue$3.run(Unknown Source)
    at java.awt.EventQueue$3.run(Unknown Source)
    at java.security.AccessController.doPrivileged(Native Method)
    at java.security.ProtectionDomain$JavaSecurityAccessImpl.doIntersectionPrivilege(Unknown Source)
    at java.security.ProtectionDomain$JavaSecurityAccessImpl.doIntersectionPrivilege(Unknown Source)
    at java.awt.EventQueue$4.run(Unknown Source)
    at java.awt.EventQueue$4.run(Unknown Source)
    at java.security.AccessController.doPrivileged(Native Method)
    at java.security.ProtectionDomain$JavaSecurityAccessImpl.doIntersectionPrivilege(Unknown Source)
    at java.awt.EventQueue.dispatchEvent(Unknown Source)
    at java.awt.EventDispatchThread.pumpOneEventForFilters(Unknown Source)
    at java.awt.EventDispatchThread.pumpEventsForFilter(Unknown Source)
    at java.awt.EventDispatchThread.pumpEventsForHierarchy(Unknown Source)
    at java.awt.EventDispatchThread.pumpEvents(Unknown Source)
    at java.awt.EventDispatchThread.pumpEvents(Unknown Source)
    at java.awt.EventDispatchThread.run(Unknown Source)
Caused by: java.lang.ClassNotFoundException: javax.websocket.DeploymentException
    at sun.plugin2.applet.Plugin2ClassLoader$2.run(Unknown Source)
    at sun.plugin2.applet.Plugin2ClassLoader$2.run(Unknown Source)
    at java.security.AccessController.doPrivileged(Native Method)
    at sun.plugin2.applet.Plugin2ClassLoader.findClassHelper(Unknown Source)
    at sun.plugin2.applet.JNLP2ClassLoader.findClass(Unknown Source)
    at sun.plugin2.applet.Plugin2ClassLoader.loadClass0(Unknown Source)
    at sun.plugin2.applet.Plugin2ClassLoader.loadClass(Unknown Source)
    at sun.plugin2.applet.Plugin2ClassLoader.loadClass(Unknown Source)
    at java.lang.ClassLoader.loadClass(Unknown Source)
    ... 24 more

Jnlp file:

<%@ page contentType="application/x-java-jnlp-file"%>
<?xml version="1.0" encoding="UTF-8"?>
<jnlp spec="1.5" codebase="http://localhost:7001/root">
    <information>
        <title>title</title>
        <vendor>vendor</vendor>
    </information>
    <security>
        <all-permissions/>
    </security>
    <resources>
        <java version="1.7*"/>
        <jar href="my_applet.jar" main="true"/>
        <jar href="tyrus-websocket-core-1.1.jar"/>
        <jar href="activation-1.1.jar"/>
        <jar href="tyrus-container-grizzly-1.2.1.jar"/>
        <jar href="tyrus-core-1.1.jar"/>
        <jar href="tyrus-server-1.1.jar"/>
        <jar href="tyrus-spi-1.2.1.jar"/>
        <jar href="grizzly-framework-2.3.3.jar"/>
        <jar href="grizzly-http-2.3.3.jar"/>
        <jar href="grizzly-http-server-2.3.3.jar"/>
        <jar href="grizzly-rcm-2.3.3.jar"/>
        <jar href="javaee-api-7.0.jar"/>
        <jar href="javax.mail-1.5.0.jar"/>
        <jar href="jnlp-api-7.0.jar"/>
        <jar href="javax.websocket-api-1.0.jar"/>
    </resources>
    <applet-desc main-class="myPackage.MyApplet" name="name" width="100" height="10">
</applet-desc>

The jars given in the jnlp-file are exactly the same as in the Java Build Path specified in eclipse. The jar files are deployed on the server, I can access them with my web browser.

My idea would be that it has something to do with the websockets-api, which fails to load the tyrus implementation at runtime, but I have no idea how to fix it.

Solution

  • Turns out the error was caused by the Trusted-Library attribute in my MANIFEST.MF file. So, if anybody is having similar problems, check that your manifest file does not contain any errors and is consistent with your jnlp file.