If you want to use java, and this is a web application (UI in the browser), you need to use the applet. I do not know another way. And this applet must be signed with a certificate. Also, the user must accept this certificate in order to allow java sound api access to the client device.
Or you can create a Java launcher application (JNLP) that will download and run on the client PC. But this will not be a website.