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/* * Copyright 2013-2019 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.config; import java.lang.reflect.Method; import java.util.Map.Entry; import org.springframework.beans.factory.FactoryBean; import org.springframework.context.expression.BeanFactoryResolver; import org.springframework.context.expression.MapAccessor; import org.springframework.expression.BeanResolver; import org.springframework.expression.PropertyAccessor; import org.springframework.expression.TypeLocator; import org.springframework.expression.spel.support.StandardEvaluationContext; import org.springframework.integration.context.IntegrationContextUtils; /** * <p> * {@link FactoryBean} to populate {@link StandardEvaluationContext} instances enhanced with: * <ul> * <li> * a {@link BeanFactoryResolver}. * </li> * <li> * a {@link org.springframework.expression.TypeConverter} based on the * {@link org.springframework.core.convert.ConversionService} from the application context. * </li> * <li> * a set of provided {@link PropertyAccessor}s including a default {@link MapAccessor}. * </li> * <li> * a set of provided SpEL functions. * </li> * </ul> * <p> * After initialization this factory populates functions and property accessors from * {@link SpelFunctionFactoryBean}s and * {@link org.springframework.integration.expression.SpelPropertyAccessorRegistrar}, * respectively. * Functions and property accessors are also inherited from any parent context. * </p> * <p> * This factory returns a new instance for each reference - {@link #isSingleton()} returns false. * </p> * * @author Artem Bilan * @author Gary Russell * * @since 3.0 */ public class IntegrationEvaluationContextFactoryBean extends AbstractEvaluationContextFactoryBean implements FactoryBean<StandardEvaluationContext> { private volatile TypeLocator typeLocator; private BeanResolver beanResolver; public void setTypeLocator(TypeLocator typeLocator) { this.typeLocator = typeLocator; } @Override public boolean isSingleton() { return false; } @Override public void afterPropertiesSet() { if (getApplicationContext() != null) { this.beanResolver = new BeanFactoryResolver(getApplicationContext()); } initialize(IntegrationContextUtils.INTEGRATION_EVALUATION_CONTEXT_BEAN_NAME); } @Override public StandardEvaluationContext getObject() { StandardEvaluationContext evaluationContext = new StandardEvaluationContext(); if (this.typeLocator != null) { evaluationContext.setTypeLocator(this.typeLocator); } evaluationContext.setBeanResolver(this.beanResolver); evaluationContext.setTypeConverter(getTypeConverter()); for (PropertyAccessor propertyAccessor : getPropertyAccessors().values()) { evaluationContext.addPropertyAccessor(propertyAccessor); } evaluationContext.addPropertyAccessor(new MapAccessor()); for (Entry<String, Method> functionEntry : getFunctions().entrySet()) { evaluationContext.registerFunction(functionEntry.getKey(), functionEntry.getValue()); } return evaluationContext; } @Override public Class<?> getObjectType() { return StandardEvaluationContext.class; } }