问如何编写netflix zuul过滤器来更改响应位置标头属性？

EN

@Override
public String filterType() {
    return "post";
}

@Override
public int filterOrder() {
    return 0;
}

@Override
public boolean shouldFilter() {
    int status = RequestContext.getCurrentContext().getResponseStatusCode();
    return status >= 300 && status < 400;
}

@Override
public Object run() {
    RequestContext ctx = RequestContext.getCurrentContext();
    Map<String, String> requestHeaders = ctx.getZuulRequestHeaders();
    Optional<Pair<String, String>> locationHeader = ctx.getZuulResponseHeaders()
                .stream()
                .filter(stringStringPair -> LOCATION.equals(stringStringPair.first()))
                .findFirst();

        if (locationHeader.isPresent()) {
            String oldLocation = locationHeader.get().second();
            String newLocation = ...
            locationHeader.get().setSecond(newLocation);
        }
    return null;
}