How to use org.springframework.web.server

  @SuppressWarnings("unchecked")
  @Override
  public <T extends Principal> Mono<T> getPrincipal() {
    return (this.principalMono != null ? (Mono<T>) this.principalMono : getDelegate().getPrincipal());
  }
}

@Override
public Mono<MultiValueMap<String, String>> getFormData() {
  return getDelegate().getFormData();
}

@Override
public ApplicationContext getApplicationContext() {
  return getDelegate().getApplicationContext();
}

@Override
public Mono<Void> filter(ServerWebExchange exchange, WebFilterChain chain) {
  ServerHttpRequest request = exchange.getRequest();
  if (hasForwardedHeaders(request)) {
    exchange = exchange.mutate().request(apply(request)).build();
  }
  return chain.filter(exchange);
}

  @Override
  public Mono<Void> filter(ServerWebExchange exchange, WebFilterChain chain) {
    exchange = exchange.mutate().principal(this.userMono).build();
    return chain.filter(exchange);
  }
}

@Override
public ServerHttpRequest getRequest() {
  return (this.request != null ? this.request : getDelegate().getRequest());
}

@Override
public ServerHttpRequest getRequest() {
  return getDelegate().getRequest();
}

@Override
public ServerHttpResponse getResponse() {
  return (this.response != null ? this.response : getDelegate().getResponse());
}

@Override
public ServerHttpResponse getResponse() {
  return getDelegate().getResponse();
}

@Override
public Map<String, Object> getAttributes() {
  return getDelegate().getAttributes();
}

@Override
public Mono<WebSession> getSession() {
  return getDelegate().getSession();
}

@Override
public <T extends Principal> Mono<T> getPrincipal() {
  return getDelegate().getPrincipal();
}

@Override
public Mono<MultiValueMap<String, Part>> getMultipartData() {
  return getDelegate().getMultipartData();
}

@Override
public boolean checkNotModified(String etag) {
  return getDelegate().checkNotModified(etag);
}

@Override
public String transformUrl(String url) {
  return getDelegate().transformUrl(url);
}

@Override
public String getLogPrefix() {
  return getDelegate().getLogPrefix();
}

@Override
public void addUrlTransformer(Function<String, String> transformer) {
  getDelegate().addUrlTransformer(transformer);
}

@Override
public boolean isNotModified() {
  return getDelegate().isNotModified();
}

@Override
public LocaleContext getLocaleContext() {
  return getDelegate().getLocaleContext();
}

@Override
public boolean checkNotModified(Instant lastModified) {
  return getDelegate().checkNotModified(lastModified);
}