Getting Java variables with Javascript, is it cross browser?

I run my applet like :

<app开发者_StackOverflowlet code="applet.class" codebase="." name="app" width="400" height="250"></applet>

and then I this in javascript to get a variable:

var string = document.app.getStringX();

I've tested it on the browsers I have and it works fine, but does someone knows if this could fail in some browsers?

It will not work in any browser that does not have Javascript and/or Java enabled.