code: public static boolean isLimitedProxy(GSIConstants.CertificateType certType) {
          return certType == GSIConstants.CertificateType.GSI_3_LIMITED_PROXY
                  || certType == GSIConstants.CertificateType.GSI_2_LIMITED_PROXY
                  || certType == GSIConstants.CertificateType.GSI_4_LIMITED_PROXY;
      }
docs: Determines if a specified certificate type indicates a GSI-2 or GSI-3 or
  GSI=4 limited proxy certificate.
  
  @param certType the certificate type to check.
  @return true if certType is a GSI-2 or GSI-3 or GSI-4 limited proxy,
  false otherwise.