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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.integration.handler; import java.lang.annotation.Annotation; import java.lang.reflect.Method; import org.springframework.beans.factory.BeanFactory; import org.springframework.context.Lifecycle; import org.springframework.core.convert.ConversionService; import org.springframework.integration.handler.support.MessagingMethodInvokerHelper; import org.springframework.integration.support.utils.IntegrationUtils; import org.springframework.lang.Nullable; import org.springframework.messaging.Message; /** * A MessageProcessor implementation that invokes a method on a target Object. * The Method instance or method name may be provided as a constructor argument. * If a method name is provided, and more than one declared method has that name, * the method-selection will be dynamic, based on the underlying SpEL method resolution. * Alternatively, an annotation type may be provided so that the candidates for * SpEL's method resolution are determined by the presence of that * annotation rather than the method name. * * @author Dave Syer * @author Artem Bilan * @author Gary Russell * * @since 2.0 */ public class MethodInvokingMessageProcessor<T> extends AbstractMessageProcessor<T> implements Lifecycle { private final MessagingMethodInvokerHelper delegate; public MethodInvokingMessageProcessor(Object targetObject, Method method) { this.delegate = new MessagingMethodInvokerHelper(targetObject, method, false); } public MethodInvokingMessageProcessor(Object targetObject, String methodName) { this.delegate = new MessagingMethodInvokerHelper(targetObject, methodName, false); } public MethodInvokingMessageProcessor(Object targetObject, String methodName, boolean canProcessMessageList) { this.delegate = new MessagingMethodInvokerHelper(targetObject, methodName, canProcessMessageList); } public MethodInvokingMessageProcessor(Object targetObject, Class<? extends Annotation> annotationType) { this.delegate = new MessagingMethodInvokerHelper(targetObject, annotationType, false); } @Override public void setConversionService(ConversionService conversionService) { super.setConversionService(conversionService); this.delegate.setConversionService(conversionService); } @Override public void setBeanFactory(BeanFactory beanFactory) { super.setBeanFactory(beanFactory); this.delegate.setBeanFactory(beanFactory); } /** * A {@code boolean} flag to use SpEL Expression evaluation or * {@link org.springframework.messaging.handler.invocation.InvocableHandlerMethod} * for target method invocation. * @param useSpelInvoker to use SpEL Expression evaluation or not. * @since 5.0 */ public void setUseSpelInvoker(boolean useSpelInvoker) { this.delegate.setUseSpelInvoker(useSpelInvoker); } @Override public void start() { this.delegate.start(); } @Override public void stop() { this.delegate.stop(); } @Override public boolean isRunning() { return this.delegate.isRunning(); } @Override @Nullable @SuppressWarnings("unchecked") public T processMessage(Message<?> message) { try { return (T) this.delegate.process(message); } catch (Exception ex) { throw IntegrationUtils.wrapInHandlingExceptionIfNecessary(message, () -> "error occurred during processing message in 'MethodInvokingMessageProcessor' [" + this + ']', ex); } } }