/*
* 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 static org.mule.expression.ExpressionConstants.ALL_ARGUMENT;
import static org.mule.expression.ExpressionConstants.DELIM;
import static org.mule.expression.ExpressionConstants.OPTIONAL_ARGUMENT;
import org.mule.api.MuleMessage;
import org.mule.api.expression.ExpressionEvaluator;
import org.mule.api.expression.RequiredValueException;
import org.mule.config.i18n.CoreMessages;
import org.mule.routing.filters.WildcardFilter;
import java.util.Collections;
import java.util.HashMap;
import java.util.Map;
import java.util.StringTokenizer;
import javax.activation.DataHandler;
/**
* Looks up the attachment(s) on the message using the expression given. The
* expression can contain a comma-separated list of header names to lookup. A
* <code>java.util.Map<String, DataHandler></code> of key value pairs is
* returned.
*
* @see MessageAttachmentsListExpressionEvaluator
* @see MessageAttachmentExpressionEvaluator
* @see ExpressionEvaluator
* @see DefaultExpressionManager
*/
public class MessageAttachmentsExpressionEvaluator implements ExpressionEvaluator
{
public static final String NAME = "attachments";
public Object evaluate(String expression, MuleMessage message)
{
boolean required;
Map<String, DataHandler> result;
//Enable wildcard matching
if (expression.contains(ALL_ARGUMENT))
{
WildcardFilter filter = new WildcardFilter(expression);
result = new HashMap<String, DataHandler>(message.getInboundAttachmentNames().size());
for (String name : message.getInboundAttachmentNames())
{
if (filter.accept(name))
{
result.put(name, message.getInboundAttachment(name));
}
}
}
else
{
StringTokenizer tokenizer = new StringTokenizer(expression, DELIM);
result = new HashMap<String, DataHandler>(tokenizer.countTokens());
while (tokenizer.hasMoreTokens())
{
String s = tokenizer.nextToken();
s = s.trim();
if (s.endsWith(OPTIONAL_ARGUMENT))
{
s = s.substring(0, s.length() - OPTIONAL_ARGUMENT.length());
required = false;
}
else
{
required = true;
}
DataHandler val = message.getInboundAttachment(s);
if (val != null)
{
result.put(s, val);
}
else if (required)
{
throw new RequiredValueException(CoreMessages.expressionEvaluatorReturnedNull(NAME, expression));
}
}
}
if (result.size() == 0)
{
return Collections.unmodifiableMap(Collections.<String, DataHandler>emptyMap());
}
else
{
return Collections.unmodifiableMap(result);
}
}
/**
* {@inheritDoc}
*/
public String getName()
{
return NAME;
}
}