/*
* Copyright 2002-2017 the original author or authors.
*
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
* You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
package org.springframework.web.reactive.result.method.annotation;
import java.util.Optional;
import org.springframework.core.MethodParameter;
import org.springframework.core.ReactiveAdapterRegistry;
import org.springframework.http.HttpMethod;
import org.springframework.http.server.reactive.ServerHttpRequest;
import org.springframework.http.server.reactive.ServerHttpResponse;
import org.springframework.web.reactive.BindingContext;
import org.springframework.web.reactive.result.method.HandlerMethodArgumentResolverSupport;
import org.springframework.web.reactive.result.method.SyncHandlerMethodArgumentResolver;
import org.springframework.web.server.ServerWebExchange;
/**
* Resolves ServerWebExchange-related method argument values of the following types:
* <ul>
* <li>{@link ServerWebExchange}
* <li>{@link ServerHttpRequest}
* <li>{@link ServerHttpResponse}
* <li>{@link HttpMethod}
* </ul>
*
* <p>For the {@code WebSession} see {@link WebSessionArgumentResolver}
* and for the {@code Principal} see {@link PrincipalArgumentResolver}.
*
* @author Rossen Stoyanchev
* @since 5.0
* @see WebSessionArgumentResolver
* @see PrincipalArgumentResolver
*/
public class ServerWebExchangeArgumentResolver extends HandlerMethodArgumentResolverSupport
implements SyncHandlerMethodArgumentResolver {
public ServerWebExchangeArgumentResolver(ReactiveAdapterRegistry adapterRegistry) {
super(adapterRegistry);
}
@Override
public boolean supportsParameter(MethodParameter parameter) {
return checkParameterTypeNoReactiveWrapper(parameter,
type -> ServerWebExchange.class.isAssignableFrom(type) ||
ServerHttpRequest.class.isAssignableFrom(type) ||
ServerHttpResponse.class.isAssignableFrom(type) ||
HttpMethod.class == type);
}
@Override
public Optional<Object> resolveArgumentValue(MethodParameter methodParameter,
BindingContext context, ServerWebExchange exchange) {
Class<?> paramType = methodParameter.getParameterType();
if (ServerWebExchange.class.isAssignableFrom(paramType)) {
return Optional.of(exchange);
}
else if (ServerHttpRequest.class.isAssignableFrom(paramType)) {
return Optional.of(exchange.getRequest());
}
else if (ServerHttpResponse.class.isAssignableFrom(paramType)) {
return Optional.of(exchange.getResponse());
}
else if (HttpMethod.class == paramType) {
return Optional.of(exchange.getRequest().getMethod());
}
else {
// should never happen...
throw new IllegalArgumentException("Unknown parameter type: " +
paramType + " in method: " + methodParameter.getMethod());
}
}
}