Issues with CheerpJ JNLP Runner
Hello all. My company has an old Java app that requires Java 8 version 171. I'm hoping that JNLP Runner can help with this. I've installed the extension and when I go to our site and run the JNLP file, it opens correctly and brings the app up but I don't get the login screen I should get, I just have the background and the right-click menu. When I open the file directly in Java it brings up the login screen. I'm not sure if there is a way to force it to use 8.171 or if this is just not something that will work with our situation. Any help would be appreciated as this would resolve one of our larger issues right now. Thanks!
4 Replies
Hello 👋 Is the application available over a public URL so we can investigate the issue for you?
If not, we would like you to save some browser log files and share them here to help us look into the problem. Can you please save the browser console log and the network HAR file? We have documentation on how to save these files here:
https://cheerpj.com/docs/guides/cheerpj-debug#saving-the-browser-console-output
https://cheerpj.com/docs/guides/cheerpj-debug#extracting-a-har-file
Please make sure to open the developer tools before pressing Start Application on the JNLPRunner page to make sure all the log files are complete.
Thanks for your help! Sadly, the URL is not public, but I have attached the requested files and I can perform any testing needed. Thanks again!
Hey, thank you for forwarding us the files. It seems the Java application makes use of low level Java Sockets which currently are not supported by CheerpJ. We do support a wider range of networking with Tailscale, which is a VPN technology using WebSockets. You can read more about it in our documentation here: https://cheerpj.com/docs/guides/Networking
When using Tailscale together with CheerpJ it is required to pass certain configuration parameters to CheerpJ when it initialises, which is currently not supported by the extension. But this can be achieved using CheerpJ Core, our standalone solution. That means you would need to change the deployment of your application from Java Web Start to a classic web application. We have an example of how this looks here: https://cheerpj.com/docs/getting-started/JNLP
This is great information. Thanks! I will check out those links and see if there is something we can do. I really appreciate your help.