/*
* $Id: MuleContextExpressionEvaluator.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.expression;
import org.mule.RequestContext;
import org.mule.api.MuleContext;
import org.mule.api.MuleEventContext;
import org.mule.api.MuleMessage;
import org.mule.api.MuleRuntimeException;
import org.mule.api.context.MuleContextAware;
import org.mule.api.expression.ExpressionEvaluator;
import org.mule.api.service.Service;
import org.mule.config.i18n.CoreMessages;
/**
* This property extractor exposes mule context information as expressions. This can be context information about
* the server itself such as the server id or about the current request such as the current service name.
* <ul>
* <li>serviceName - returns the name of the service currently processing the event.</li>
* <li>modelName - returns the name of the model that hosts the current service</li>
* <li>inboundEndpoint - returns the URI string of the endpoint that received the current messgae.</li>
* <li>serverId - the Mule instance server Id.</li>
* <li>clusterId - the Mule instance cluster Id.</li>
* <li>domainId - the Mule instance domain Id.</li>
* <li>workingDir - Mule's working directory.</li>
* <li>homeDir - Mule's home directory</li>
* </ul>
*/
public class MuleContextExpressionEvaluator implements ExpressionEvaluator, MuleContextAware
{
public static final String NAME = "context";
protected MuleContext muleContext;
public void setMuleContext(MuleContext context)
{
this.muleContext = context;
}
/**
* Extracts a single property from the message
*
* @param expression the property expression or expression
* @param message the message to extract from
* @return the result of the extraction or null if the property was not found
*/
public Object evaluate(String expression, MuleMessage message)
{
if (expression.equals("serviceName"))
{
return getEventContext().getFlowConstruct().getName();
}
else if (expression.equals("modelName"))
{
if (getEventContext().getFlowConstruct() instanceof Service)
{
return ((Service) getEventContext().getFlowConstruct()).getModel().getName();
}
else
{
throw new UnsupportedOperationException("The 'modelName' function can only be used with Service");
}
}
else if (expression.equals("inboundEndpoint"))
{
return getEventContext().getEndpointURI();
}
else if (expression.equals("serverId"))
{
return getMuleContext().getConfiguration().getId();
}
else if (expression.equals("clusterId"))
{
return getMuleContext().getConfiguration().getClusterId();
}
else if (expression.equals("domainId"))
{
return getMuleContext().getConfiguration().getDomainId();
}
else if (expression.equals("workingDir"))
{
return getMuleContext().getConfiguration().getWorkingDirectory();
}
else if (expression.equals("homeDir"))
{
return getMuleContext().getConfiguration().getMuleHomeDirectory();
}
else
{
throw new IllegalArgumentException(expression);
}
}
protected MuleContext getMuleContext()
{
return muleContext;
}
protected MuleEventContext getEventContext()
{
if(RequestContext.getEventContext()==null)
{
throw new MuleRuntimeException(CoreMessages.objectIsNull("MuleEventContext"));
}
else
{
return RequestContext.getEventContext();
}
}
/**
* Gts the name of the object
*
* @return the name of the object
*/
public String getName()
{
return NAME;
}
/**
* Sets the name of the object
*
* @param name the name of the object
*/
public void setName(String name)
{
throw new UnsupportedOperationException();
}
}