/*
* Copyright 2002-2016 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.integration.aggregator;
import org.springframework.beans.BeansException;
import org.springframework.beans.factory.BeanFactory;
import org.springframework.beans.factory.BeanFactoryAware;
import org.springframework.expression.Expression;
import org.springframework.expression.ExpressionParser;
import org.springframework.expression.spel.SpelParserConfiguration;
import org.springframework.expression.spel.standard.SpelExpressionParser;
import org.springframework.integration.handler.ExpressionEvaluatingMessageProcessor;
import org.springframework.messaging.Message;
import org.springframework.util.Assert;
/**
* {@link CorrelationStrategy} implementation that evaluates an expression.
*
* @author Dave Syer
* @author Oleg Zhurakousky
* @author Artem Bilan
*/
public class ExpressionEvaluatingCorrelationStrategy implements CorrelationStrategy, BeanFactoryAware {
private static final ExpressionParser expressionParser = new SpelExpressionParser(new SpelParserConfiguration(true, true));
private final ExpressionEvaluatingMessageProcessor<Object> processor;
public ExpressionEvaluatingCorrelationStrategy(String expressionString) {
Assert.hasText(expressionString, "expressionString must not be empty");
Expression expression = expressionParser.parseExpression(expressionString);
this.processor = new ExpressionEvaluatingMessageProcessor<Object>(expression, Object.class);
}
public ExpressionEvaluatingCorrelationStrategy(Expression expression) {
this.processor = new ExpressionEvaluatingMessageProcessor<Object>(expression, Object.class);
}
public Object getCorrelationKey(Message<?> message) {
return this.processor.processMessage(message);
}
public void setBeanFactory(BeanFactory beanFactory) throws BeansException {
if (beanFactory != null) {
this.processor.setBeanFactory(beanFactory);
}
}
}