public void addAndValidate(String headerName, String value) {
        String normalName = HeaderName.normalize(Objects.requireNonNull(headerName, "headerName"));
        Objects.requireNonNull(value, "value");
        addNormal(validateField(headerName), validateField(normalName), validateField(value));
    }
Adds the name and value to the headers and validate.

@throws ZuulException on invalid name or value
zuul-core/src/main/java/com/netflix/zuul/message/Headers.java