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/* * Copyright 2002-2019 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 * * https://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.messaging.handler.annotation.support; import java.lang.reflect.Method; import java.util.ArrayList; import java.util.List; import org.springframework.beans.factory.BeanFactory; import org.springframework.beans.factory.BeanFactoryAware; import org.springframework.beans.factory.InitializingBean; import org.springframework.beans.factory.config.ConfigurableBeanFactory; import org.springframework.core.convert.ConversionService; import org.springframework.format.support.DefaultFormattingConversionService; import org.springframework.lang.Nullable; import org.springframework.messaging.converter.GenericMessageConverter; import org.springframework.messaging.converter.MessageConverter; import org.springframework.messaging.handler.invocation.HandlerMethodArgumentResolver; import org.springframework.messaging.handler.invocation.HandlerMethodArgumentResolverComposite; import org.springframework.messaging.handler.invocation.InvocableHandlerMethod; import org.springframework.util.Assert; import org.springframework.validation.Validator; /** * The default {@link MessageHandlerMethodFactory} implementation creating an * {@link InvocableHandlerMethod} with the necessary * {@link HandlerMethodArgumentResolver} instances to detect and process * most of the use cases defined by * {@link org.springframework.messaging.handler.annotation.MessageMapping MessageMapping}. * * <p>Extra method argument resolvers can be added to customize the method * signature that can be handled. * * <p>By default, the validation process redirects to a no-op implementation, see * {@link #setValidator(Validator)} to customize it. The {@link ConversionService} * can be customized in a similar manner to tune how the message payload * can be converted * * @author Stephane Nicoll * @author Juergen Hoeller * @since 4.1 * @see #setConversionService * @see #setValidator * @see #setCustomArgumentResolvers */ public class DefaultMessageHandlerMethodFactory implements MessageHandlerMethodFactory, BeanFactoryAware, InitializingBean { private ConversionService conversionService = new DefaultFormattingConversionService(); @Nullable private MessageConverter messageConverter; @Nullable private Validator validator; @Nullable private List<HandlerMethodArgumentResolver> customArgumentResolvers; private final HandlerMethodArgumentResolverComposite argumentResolvers = new HandlerMethodArgumentResolverComposite(); @Nullable private BeanFactory beanFactory; /** * Set the {@link ConversionService} to use to convert the original * message payload or headers. * @see HeaderMethodArgumentResolver * @see GenericMessageConverter */ public void setConversionService(ConversionService conversionService) { this.conversionService = conversionService; } /** * Set the {@link MessageConverter} to use. By default a {@link GenericMessageConverter} * is used. * @see GenericMessageConverter */ public void setMessageConverter(MessageConverter messageConverter) { this.messageConverter = messageConverter; } /** * Set the Validator instance used for validating {@code @Payload} arguments. * @see org.springframework.validation.annotation.Validated * @see PayloadMethodArgumentResolver */ public void setValidator(Validator validator) { this.validator = validator; } /** * Set the list of custom {@code HandlerMethodArgumentResolver}s that will be used * after resolvers for supported argument type. * @param customArgumentResolvers the list of resolvers (never {@code null}) */ public void setCustomArgumentResolvers(List<HandlerMethodArgumentResolver> customArgumentResolvers) { this.customArgumentResolvers = customArgumentResolvers; } /** * Configure the complete list of supported argument types effectively overriding * the ones configured by default. This is an advanced option. For most use cases * it should be sufficient to use {@link #setCustomArgumentResolvers(java.util.List)}. */ @SuppressWarnings("ConstantConditions") public void setArgumentResolvers(List<HandlerMethodArgumentResolver> argumentResolvers) { if (argumentResolvers == null) { this.argumentResolvers.clear(); return; } this.argumentResolvers.addResolvers(argumentResolvers); } /** * A {@link BeanFactory} only needs to be available for placeholder resolution * in handler method arguments; it's optional otherwise. */ @Override public void setBeanFactory(BeanFactory beanFactory) { this.beanFactory = beanFactory; } @Override public void afterPropertiesSet() { if (this.messageConverter == null) { this.messageConverter = new GenericMessageConverter(this.conversionService); } if (this.argumentResolvers.getResolvers().isEmpty()) { this.argumentResolvers.addResolvers(initArgumentResolvers()); } } @Override public InvocableHandlerMethod createInvocableHandlerMethod(Object bean, Method method) { InvocableHandlerMethod handlerMethod = new InvocableHandlerMethod(bean, method); handlerMethod.setMessageMethodArgumentResolvers(this.argumentResolvers); return handlerMethod; } protected List<HandlerMethodArgumentResolver> initArgumentResolvers() { List<HandlerMethodArgumentResolver> resolvers = new ArrayList<>(); ConfigurableBeanFactory beanFactory = (this.beanFactory instanceof ConfigurableBeanFactory ? (ConfigurableBeanFactory) this.beanFactory : null); // Annotation-based argument resolution resolvers.add(new HeaderMethodArgumentResolver(this.conversionService, beanFactory)); resolvers.add(new HeadersMethodArgumentResolver()); // Type-based argument resolution resolvers.add(new MessageMethodArgumentResolver(this.messageConverter)); if (this.customArgumentResolvers != null) { resolvers.addAll(this.customArgumentResolvers); } Assert.notNull(this.messageConverter, "MessageConverter not configured"); resolvers.add(new PayloadMethodArgumentResolver(this.messageConverter, this.validator)); return resolvers; } }