为了编写GatewayFilter，您将需要实现GatewayFilterFactory。您可以扩展名为AbstractGatewayFilterFactory的抽象类。

PreGatewayFilterFactory.java。 

public class PreGatewayFilterFactory extends AbstractGatewayFilterFactory<PreGatewayFilterFactory.Config> {

	public PreGatewayFilterFactory() {
		super(Config.class);
	}

	@Override
	public GatewayFilter apply(Config config) {
		// grab configuration from Config object
		return (exchange, chain) -> {
			//If you want to build a "pre" filter you need to manipulate the
			//request before calling chain.filter
			ServerHttpRequest.Builder builder = exchange.getRequest().mutate();
			//use builder to manipulate the request
			return chain.filter(exchange.mutate().request(request).build());
		};
	}

	public static class Config {
		//Put the configuration properties for your filter here
	}

}

PostGatewayFilterFactory.java。 

public class PostGatewayFilterFactory extends AbstractGatewayFilterFactory<PostGatewayFilterFactory.Config> {

	public PostGatewayFilterFactory() {
		super(Config.class);
	}

	@Override
	public GatewayFilter apply(Config config) {
		// grab configuration from Config object
		return (exchange, chain) -> {
			return chain.filter(exchange).then(Mono.fromRunnable(() -> {
				ServerHttpResponse response = exchange.getResponse();
				//Manipulate the response in some way
			}));
		};
	}

	public static class Config {
		//Put the configuration properties for your filter here
	}

}