001/* 002 * Copyright 2002-2018 the original author or authors. 003 * 004 * Licensed under the Apache License, Version 2.0 (the "License"); 005 * you may not use this file except in compliance with the License. 006 * You may obtain a copy of the License at 007 * 008 * https://www.apache.org/licenses/LICENSE-2.0 009 * 010 * Unless required by applicable law or agreed to in writing, software 011 * distributed under the License is distributed on an "AS IS" BASIS, 012 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. 013 * See the License for the specific language governing permissions and 014 * limitations under the License. 015 */ 016 017package org.springframework.messaging.handler.invocation.reactive; 018 019import reactor.core.publisher.Mono; 020 021import org.springframework.core.MethodParameter; 022import org.springframework.messaging.Message; 023 024/** 025 * Strategy interface for resolving method parameters into argument values 026 * in the context of a given {@link Message}. 027 * 028 * @author Rossen Stoyanchev 029 * @since 5.2 030 */ 031public interface HandlerMethodArgumentResolver { 032 033 /** 034 * Whether the given {@linkplain MethodParameter method parameter} is 035 * supported by this resolver. 036 * @param parameter the method parameter to check 037 * @return {@code true} if this resolver supports the supplied parameter; 038 * {@code false} otherwise 039 */ 040 boolean supportsParameter(MethodParameter parameter); 041 042 /** 043 * Resolves a method parameter into an argument value from a given message. 044 * @param parameter the method parameter to resolve. 045 * This parameter must have previously been passed to 046 * {@link #supportsParameter(org.springframework.core.MethodParameter)} 047 * which must have returned {@code true}. 048 * @param message the currently processed message 049 * @return {@code Mono} for the argument value, possibly empty 050 */ 051 Mono<Object> resolveArgument(MethodParameter parameter, Message<?> message); 052 053}