JSF Tip of the Day: Reading Authorization Header in JSF

After I did the JAX-RS Tip of the Day today, I wondered about reading the authorization header from JSF. The technique is the same as the JAX-RS version, but the methods are different depending on what is available to the JSF application. The JAX-RS Base64 class is not part of the web profile in Java EE 6. It will be part of Java EE 7 so you could use it. I chose to add the comments in the code below, but decided that I would use the com.sun.misc.Base64Decoder which is currently available in Java SE 6 and 7.
UPDATE: I got a suggestion on Google+ from +Thomas Darimont who mentioned using DatatypeConverter.parseBase64Binary() from the Java API for XML Binding (JAXB). I confirmed that it is available in Java EE 5 and 6. It is also in the Web Profile in Java EE 6.