Java applications on the website

I have a question about getting my application on to a website. Basically, when I code something in Java and it works as a stand-alone GUI application through the JVM, how do I add that program to a webpage?

I will assume the most basic things are:
1. Buy/rent a web address (i.e. a service to host my webpage).
2. Purchase enough space on that host's server to hold a small database (text only).
3. Make the webpage via html+javascript
4. Add my source code to the webpage.

So my questions happen one number 3 and 4. What does html and javascript code look like to surround java code (the application)?

Brightmatter

P.S. perhaps making the GUI in javascript is easier?

You can't just plop Java into a web page. Your choices:

Java Web Start, which downloads a desktop app to run on the client outside the browser.

Applets, run in the browser on the client.

Servlets/JSP, execute on the server to generate dynamic HTML pages to send to the client.