code: public static URI getUserURI(final String sessionUserId) {
          // user id could be in format <anonymous>, remove < at the beginning and the > at the end in this case.
          final String userId = (sessionUserId == null ? "anonymous" : sessionUserId).replaceAll("^<|>$", "");
          try {
              final URI uri = URI.create(userId);
              // return useId if it's an absolute URI or an opaque URI
              if (uri.isAbsolute() || uri.isOpaque()) {
                  return uri;
              } else {
                  return buildDefaultURI(userId);
              }
          } catch (final IllegalArgumentException e) {
              return buildDefaultURI(userId);
          }
      }
docs: Returns the user agent based on the session user id.
  @param sessionUserId the acting user's id for this session
  @return the uri of the user agent