code: protected void setServerProtocol(String serverProtocol) {
  
          if (CmsStringUtil.isEmpty(serverProtocol) || (WILDCARD.equals(serverProtocol))) {
              m_serverProtocol = WILDCARD;
          } else {
              int pos = serverProtocol.indexOf("/");
              if (pos > 0) {
                  m_serverProtocol = serverProtocol.substring(0, pos).toLowerCase();
              } else {
                  m_serverProtocol = serverProtocol.toLowerCase().trim();
              }
          }
      }
docs: Sets the protocol (e.g. "http", "https") which is required to access this site.<p>
  
  Setting the protocol to "*" is a wildcard that matches all protocols.<p>
  
  @param serverProtocol the protocol (e.g. "http", "https") which is required to access this site