default String extract(final HttpServletRequest request) {
        var authTokenValue = request.getParameter(TokenConstants.PARAMETER_NAME_TOKEN);
        if (StringUtils.isBlank(authTokenValue)) {
            authTokenValue = request.getHeader(TokenConstants.PARAMETER_NAME_TOKEN);
        }
        return authTokenValue;
    }
Extract string.

@param request the request
@return the string
support/cas-server-support-token-webflow/src/main/java/org/apereo/cas/web/TokenRequestExtractor.java