URI uri = exchange.getRequest().getURI();
                StringBuilder query = new StringBuilder();
                String originalQuery = uri.getRawQuery();
                if (StringUtils.hasText(originalQuery)) {
                    query.append(originalQuery);
                    if (originalQuery.charAt(originalQuery.length() - 1) != '&') {
                        query.append('&');
                    }
                }
                params.forEach((key,value) ->{
                    query.append(key);
                    query.append('=');
                    query.append(value);
                    query.append('&');
                });

                try {
                    URI newUri = UriComponentsBuilder.fromUri(uri).replaceQuery(query.toString()).build(true).toUri();
                    ServerHttpRequest request = exchange.getRequest().mutate().uri(newUri).build();
                    return chain.filter(exchange.mutate().request(request).build());
                } catch (RuntimeException var8) {
                    throw new IllegalStateException("Invalid URI query: \"" + query.toString() + "\"");
                }

以上这种写法,参考了自带的 AddRequestParameter 过滤器的写法