Using IcedTea-Web (to run JNLP) 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.

17 thoughts on “Using IcedTea-Web (to run JNLP) with AdoptOpenJDK.”

  1. This is a clutch solution, which is by no means practical for “larger” deployments (>5 machines).
    I’ll stick with Oracle Java due to this.

  2. We’re still trying to figure out if there’s a solution for running web page-embedded applets in Internet Explorer on Windows with OpenJDK. Basically, we’re trying to duplicate the functionality of ssvagent.exe and ssv.dll included with the Oracle distribution so that we can support some third-party extranet applications (don’t get me started). It looks like on Windows that IcedTea-Web is a launcher for .jnlp files which is still extremely useful and cool, but I don’t see anything that’s an actual plugin. This is probably complicated by Firefox and Chrome no longer supporting those sorts of plugins, and Internet Explorer having one foot in the grave while being of no interest whatsoever to people in the Linux / UNX world (and the rest of us won’t cry when it’s gone either). But in the meantime, we’ve got other people’s crazy ancient apps to deal with…

    1. Hi Erik, have you figured out the solution for running web page-embedded applets in Internet Explorer on Windows with OpenJDK ?

    1. Hi,

      I am not sure if you were successful in your Auto Launch mission, In case you still havn’t please follow the below steps:
      ( for Firefox browser, should work for IE as well)

      Download JNLP onto your system, click on the file so the dialog box pops us , then in the Open With pick other.. browse until you find ITW’s javaws .
      Thats all.

      If this is not the first time you have open JNLP via ITW, then you could also do the below :
      Open Firefox -> Settings -> General -> Applications : Choose ITW to open JNLPs.


  3. 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

  4. @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.


  5. 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.

  6. 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.

Leave a Reply