Interaction between JavaScript + Java

Hello people

I am developing a Web site that embeds a Signed Java Applet and I need your help with the following issue

I need some way of knowing 2 things about the user who is visiting my site
1) Whether he has the Java Runtime Environment installed
2) Whether he already accepted my Signed Java Applet

If I know the answer to these 2 questions, I will be able to decide whether I need to instruct the user about any needed installation

For example, If I can determine that the user doesn’t have JRE installed (like most users), I could display him a message describing the installation process and what needs to be done (in order to help him)
If I determine that the user already has JRE installed, I know I can skip such explanation

Also, If I know that the user didn’t accept my Signed Java Applet, I will be able to instruct him about that

I need to know whether any of these 2 information bits can become available to me in any way. This could be done in JavaScript if possible, but any other solution is also welcome

Any help or lead will be appreciated
Thanks

Also in #JavaScript _↴