Detecting mime-type registered through JNLP using navigator.mimeTypes

Question

After having installed and run a JNLP application, is it possible to use navigator.mimeTypes via javascript in a browser to detect the expected mime-type? While using Chrome on OSX we have noticed that the mime-type does not appear in the navigators list.

var isSupported = navigator.mimeTypes['application/x-my-own-app'];

This was registered via JNLP like so:

IntegrationService is = null;
try {
    is = (IntegrationService) ServiceManager.lookup("javax.jnlp.IntegrationService");
    if (!is.hasAssociation("application/x-my-own-app", new String[] { "myownapp", "moa" })) {
        if (!is.requestAssociation("application/x-my-own-app", new String[] { "myownapp", "moa" })) {
            System.err.println("Association creation failed");
        }
    }
 } catch (UnavailableServiceException use) {
     System.err.println("Integration service unavailable");
 }

If for whatever reason it is not possible to access the registered mime-type in the browser, is there another means to obtain the existence of a registration?

Edit

The process goes like this:

1. User's first visit to the page, they directed to a .jnlp link
2. JNLP app downloads and runs; it also registers its mime-type

On subsequent visits:

1. The page (javascript) checks for the mime-type registration
2. If the registration is not found the user is directed to the .jnlp link. If the registration is found they are directed to the .moa link.

Answer 1

Unfortunately the registration performed by JNLP is done so in the operating system, not in the browser. Therefore the navigator cannot provide the registration required for my use.

Answer 2

Use IntegrationService.hasAssociation(String,String[]).

So that it can be determined that the app is already installed and that we don't need to direct the user to a .jnlp file, but instead to a .moa or .myownapp item.

Use a (light, small) JNLP based applet to do the detection in the browser.