Using IcedTea Web-browser Plug-in with AdoptOpenJDK.

When Java went Open, the whole of Java developer community was like “whoo hooo!”, and everyone has been embracing OpenJDK with wide open arms. The AdoptOpenJDK community took the lead in making users life easier by providing prebuilt OpenJDK binaries from a fully open source set of build scripts and infrastructure.

However, the Java WebStart Wizard used to create the XML-based JNLP (Java Network Launching Protocol) definition file, that the Web Start software uses to download and run Java applications and applets on client machines was not Open Sourced as part of OpenJDK.

Thankfully the GNU Classpath community come up with a free software implementation of Java Web Start and the Java web browser plugin for running applets and thus our hero IcedTea-Web was born.

We have produced a short slide deck @Running Web Start Application
And a video @ Setting up AdoptOpenJDK with IcedTea-Web showing you how to get the IcedTea WebStart plugin working with AdoptOpenJDK binaries.

Voila!! Go ahead and run your WebStart applications to your heart’s content.

10 thoughts on “Using IcedTea Web-browser Plug-in with AdoptOpenJDK.”

  1. Hi, what about Proxy Settings in Iced-Tea Web ? Normally we use Proxy Settings of Internet Explorer. These are stored in the windows registry as DWord…

    1. You start the itweb-settings.bat (similar to your Java console) then under “Network” -> “Network Proxy setting” you can either use
      – Use browser setting or
      – Manual Proxy server (setup you proxy here) or

  2. @Divi_Dv02 and Eli Abramson :
    Could you please give more information on what your case is? I recently got to work on another person who was unsuccessful in launching the Java applets, he had an exception preventing him from launching the exception:

    at java.awt.EventQueue.invokeAndWait(
    at java.awt.EventQueue.invokeAndWait(
    at javax.swing.SwingUtilities.invokeAndWait(
    at net.sourceforge.jnlp.runtime.AppletEnvironment.startApplet(
    at net.sourceforge.jnlp.Launcher.launchApplet(
    at net.sourceforge.jnlp.Launcher$
    Caused by: java.lang.IllegalMonitorStateException
    at java.lang.Object.wait(Native Method)
    at java.lang.Object.wait(
    at Source)
    at exc.fe.FeLaunch.b(Unknown Source)
    at exc.fe.FeLaunch.start(Unknown Source)
    at net.sourceforge.jnlp.runtime.AppletEnvironment$
    at java.awt.event.InvocationEvent.dispatch(
    at java.awt.EventQueue.dispatchEventImpl(
    at java.awt.EventQueue.access$500(
    at java.awt.EventQueue$
    at java.awt.EventQueue$
    at Method)
    at java.awt.EventQueue.dispatchEvent(
    at java.awt.EventDispatchThread.pumpOneEventForFilters(
    at java.awt.EventDispatchThread.pumpEventsForFilter(
    at java.awt.EventDispatchThread.pumpEventsForHierarchy(
    at java.awt.EventDispatchThread.pumpEvents(
    at java.awt.EventDispatchThread.pumpEvents(

    I confirmed, we will need to raise an IcedTea-web bug for this issue.

    Step-by-step guide on how to run applets on IE using IcedTea-Web and Adopt OpenJDK:
    There are 2 ways to run your Applet (if you are on Windows by default it’ll run on IE) ..
    [After you have set your Path- add the Java Home, give your browser path as well ]
    a) Directly in the browser address, access your.jnlp and “Open With” IcedTea webstart.
    b) On command prompt run: javaws your.jnlp

    If the applets are not launching, you could start the Control panel, ie, run : itweb-settings.bat, under “Debugging” – Enable Debugging, this will give you the reason why your applet has failed to start, share that exception with us and we’ll see how we can help further.


  3. I did try these 2 resources but I’m not able to run my Java applets on IE using IcedTea-Web and Adopt OpenJDK. These resources weren’t much helpful. Can you please provide us with a step-by-step guide on how to run Java Applets on Internet Explorer using AdoptOpenJDK and IcedTea-Web.

  4. These 2 resources aren’t much helpful. I want to run Java Applets on Internet Explorer. I tried the steps mentioned here but they didn’t work. Can you please provide us with a step-by-step guide on how to run applets on IE using IcedTea-Web and Adopt OpenJDK

    1. Hi there,

      Are you able to join our slack at and we’ll try to connect you with the right expert.

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