During the 401 Java course, we will be learning a great deal of Java, SpringMVC, and Android, But we will also be making use of technologies related to web development. A solid working knowledge of HTML/CSS/JS is important for any web developer.
If you are a complete beginner, then may I suggest an account with either Treehouse or CodeAcademy. Once you are signed up, either site has a number of quality tutorials that cover HTML, CSS, and JavaScript. Pick some, and work through them. Then pick the next in line and keep going. Spend some time each day working on this.
Another great resource for all of the above is FreeCodeCamp. Once you sign up for an account there, you should be able to work your way all the way through the Advanced Algorithm Scripting section of work. It does take time though, so pace yourself over several days/weeks.