/*
* $Id: OgnlExpressionEvaluator.java 20321 2010-11-24 15:21:24Z dfeist $
* --------------------------------------------------------------------------------------
* Copyright (c) MuleSoft, Inc. All rights reserved. http://www.mulesoft.com
*
* The software in this package is published under the terms of the CPAL v1.0
* license, a copy of which has been included with this distribution in the
* LICENSE.txt file.
*/
package org.mule.module.ognl.expression;
import org.mule.api.MuleMessage;
import org.mule.api.expression.ExpressionEvaluator;
import org.mule.api.expression.ExpressionRuntimeException;
import org.mule.api.lifecycle.Disposable;
import org.mule.config.i18n.CoreMessages;
import java.util.Map;
import java.util.concurrent.ConcurrentHashMap;
import ognl.Ognl;
import ognl.OgnlException;
import org.apache.commons.logging.Log;
import org.apache.commons.logging.LogFactory;
/**
* An expression evaluator that uses OGNL as the expression language
*/
public class OgnlExpressionEvaluator implements ExpressionEvaluator, Disposable
{
Map<String, Object> expressions = new ConcurrentHashMap<String, Object>(4);
public static final String NAME = "ognl";
/**
* logger used by this class
*/
protected transient final Log logger = LogFactory.getLog(OgnlExpressionEvaluator.class);
public Object evaluate(String expression, MuleMessage message)
{
Object o = expressions.get(expression);
if(o==null)
{
try
{
o = Ognl.parseExpression(expression);
expressions.put(expression, o);
}
catch (OgnlException e)
{
throw new ExpressionRuntimeException(CoreMessages.expressionMalformed(expression, NAME), e);
}
}
try
{
return Ognl.getValue(o, message.getPayload());
}
catch (OgnlException e)
{
//Only log the exceptions so that the behaviour is consistent with the Expression API
logger.warn(e.getMessage(), e);
return null;
}
}
public void setName(String name)
{
throw new UnsupportedOperationException("setName");
}
public String getName()
{
return NAME;
}
public void dispose()
{
expressions.clear();
}
}