/*
* Copyright 2013 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.transformer.support;
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;
/**
* @author Mark Fisher
* @author Artem Bilan
* @since 3.0
*/
public class ExpressionEvaluatingHeaderValueMessageProcessor<T> extends AbstractHeaderValueMessageProcessor<T>
implements BeanFactoryAware {
private static final ExpressionParser expressionParser = new SpelExpressionParser(new SpelParserConfiguration(
true, true));
private final ExpressionEvaluatingMessageProcessor<T> targetProcessor;
/**
* Create a header value processor for the given Expression and the
* expected type of the expression evaluation result. The expectedType
* may be null if unknown.
*
* @param expression the {@link Expression} to evaluate.
* @param expectedType the type for return value of {@code expression} evaluation result.
*/
public ExpressionEvaluatingHeaderValueMessageProcessor(Expression expression, Class<T> expectedType) {
this.targetProcessor = new ExpressionEvaluatingMessageProcessor<T>(expression, expectedType);
}
/**
* Create a header value processor for the given expression string and
* the expected type of the expression evaluation result. The
* expectedType may be null if unknown.
*
* @param expressionString the {@link java.lang.String} expression presentation to evaluate.
* @param expectedType the type for return value of {@code expression} evaluation result.
*/
public ExpressionEvaluatingHeaderValueMessageProcessor(String expressionString, Class<T> expectedType) {
Expression expression = expressionParser.parseExpression(expressionString);
this.targetProcessor = new ExpressionEvaluatingMessageProcessor<T>(expression, expectedType);
}
public void setBeanFactory(BeanFactory beanFactory) {
this.targetProcessor.setBeanFactory(beanFactory);
}
public T processMessage(Message<?> message) {
return this.targetProcessor.processMessage(message);
}
}