public static void throwIfUnrecognizedParamName(final Enumeration initParamNames) {
        val recognizedParameterNames = new HashSet<String>();
        recognizedParameterNames.add(ALLOW_MULTI_VALUED_PARAMETERS);
        recognizedParameterNames.add(PARAMETERS_TO_CHECK);
        recognizedParameterNames.add(ONLY_POST_PARAMETERS);
        recognizedParameterNames.add(CHARACTERS_TO_FORBID);
        recognizedParameterNames.add(PATTERN_TO_BLOCK);


        while (initParamNames.hasMoreElements()) {
            val initParamName = (String) initParamNames.nextElement();
            if (!recognizedParameterNames.contains(initParamName)) {
                throwException(new ServletException("Unrecognized init parameter [" + initParamName + "]."));
            }
        }
    }
Examines the Filter init parameter names and throws ServletException if they contain an unrecognized
init parameter name.
<p>
This is a stateless static method.
<p>
This method is an implementation detail and is not exposed API.
This method is only non-private to allow JUnit testing.

@param initParamNames init param names, in practice as read from the FilterConfig.
core/cas-server-core-web-api/src/main/java/org/apereo/cas/web/support/filters/RequestParameterPolicyEnforcementFilter.java