/*
* Licensed to the Apache Software Foundation (ASF) under one
* or more contributor license agreements. See the NOTICE file
* distributed with this work for additional information
* regarding copyright ownership. The ASF licenses this file
* to you 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.apache.synapse.util.xpath;
import org.apache.synapse.MessageContext;
import org.apache.synapse.mediators.GetPropertyFunction;
import org.jaxen.Function;
import org.jaxen.FunctionContext;
import org.jaxen.UnresolvableException;
/**
* <p>XPath function context to be used when resolving XPath functions when using the
* <code>SynapseXPath</code> and this resolves one function except for the standard XPath functions
* and Jaxen extension functions.</p>
*
* <p>The function that has been resolved by this FunctionContext is; <tt>get-property(String)</tt>
* which is used to retrieve message context properties</p>
*
* @see org.jaxen.XPathFunctionContext
* @see org.apache.synapse.util.xpath.SynapseXPath
*/
public class SynapseXPathFunctionContext implements FunctionContext {
/** Parent function context */
private final FunctionContext parent;
/** MessageContext to be used by the function resolver */
private final MessageContext synCtx;
/**
* <p>Initialises the function context</p>
*
* @param parent the parent function context
* @param synCtx message to be used for the function initialization
*
* @see org.jaxen.XPathFunctionContext
*/
public SynapseXPathFunctionContext(FunctionContext parent, MessageContext synCtx) {
this.parent = parent;
this.synCtx = synCtx;
}
/**
* Get the function with a given namespace and name.
* <p>
* Only the <tt>get-property</tt> function is recognized by this class. Any other
* function will be resolved using the parent function context.
*
* @param namespaceURI namespace of the function to be resolved
* @param prefix string prefix to be resolved
* @param localName string local name of the function
* @return resolved function
* @throws UnresolvableException if the function specified does not found
*/
public Function getFunction(String namespaceURI, String prefix, String localName)
throws UnresolvableException {
if (localName != null && SynapseXPathConstants.GET_PROPERTY_FUNCTION.equals(localName)) {
// create an instance of a synapse:get-property()
// function and set it to the xpath
GetPropertyFunction getPropertyFunc = new GetPropertyFunction();
getPropertyFunc.setSynCtx(synCtx);
return getPropertyFunc;
}
// if not the get-property function then try to get it from the parent context
return parent.getFunction(namespaceURI, prefix, localName);
}
}