code: public String getUserAttribute(final String _key)
          throws EFapsException
      {
          if (containsSessionAttribute(UserAttributesSet.CONTEXTMAPKEY)) {
              return ((UserAttributesSet) getSessionAttribute(UserAttributesSet.CONTEXTMAPKEY)).getString(_key);
          } else {
              throw new EFapsException(Context.class, "getUserAttribute.NoSessionAttribute");
          }
      }
docs: This method retrieves a UserAttribute of the Person this Context belongs
  to. The UserAttributes are stored in the {@link #sessionAttributes} Map,
  therefore are thought to be valid for one session.
  
  @param _key key to Search for
  @return String with the value
  @throws EFapsException on error