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diff --git a/sca-java-2.x/tags/2.0.1-RC1/modules/assembly-xml/src/main/java/org/apache/tuscany/sca/policy/xml/PolicyXPathFunction.java b/sca-java-2.x/tags/2.0.1-RC1/modules/assembly-xml/src/main/java/org/apache/tuscany/sca/policy/xml/PolicyXPathFunction.java
new file mode 100644
index 0000000000..8e2d7f9e60
--- /dev/null
+++ b/sca-java-2.x/tags/2.0.1-RC1/modules/assembly-xml/src/main/java/org/apache/tuscany/sca/policy/xml/PolicyXPathFunction.java
@@ -0,0 +1,295 @@
+/*
+ * 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.tuscany.sca.policy.xml;
+
+import java.util.ArrayList;
+import java.util.Arrays;
+import java.util.HashSet;
+import java.util.List;
+import java.util.Set;
+import java.util.logging.Level;
+import java.util.logging.Logger;
+import java.util.regex.Matcher;
+import java.util.regex.Pattern;
+
+import javax.xml.XMLConstants;
+import javax.xml.namespace.NamespaceContext;
+import javax.xml.namespace.QName;
+import javax.xml.xpath.XPathFunction;
+import javax.xml.xpath.XPathFunctionException;
+
+import org.w3c.dom.Document;
+import org.w3c.dom.Node;
+import org.w3c.dom.NodeList;
+
+/**
+ * The SCA-defined XPath function
+ */
+public class PolicyXPathFunction implements XPathFunction {
+    private static Logger logger = Logger.getLogger(PolicyXPathFunction.class.getName());
+
+    static final QName InterfaceRef = new QName(PolicyConstants.SCA11_NS, "InterfaceRef");
+    static final QName OperationRef = new QName(PolicyConstants.SCA11_NS, "OperationRef");
+    static final QName MessageRef = new QName(PolicyConstants.SCA11_NS, "MessageRef");
+    static final QName IntentRefs = new QName(PolicyConstants.SCA11_NS, "IntentRefs");
+    static final QName URIRef = new QName(PolicyConstants.SCA11_NS, "URIRef");
+
+    static final Set<QName> functions =
+        new HashSet<QName>(Arrays.asList(InterfaceRef, OperationRef, MessageRef, IntentRefs, URIRef));
+
+    private NamespaceContext namespaceContext;
+    private final QName functionName;
+
+    public PolicyXPathFunction(NamespaceContext namespaceContext, QName functionName) {
+        super();
+        this.namespaceContext = namespaceContext;
+        this.functionName = functionName;
+    }
+
+    private Node getContextNode(List args) {
+        if (args.size() >= 2) {
+            NodeList nodeList = (NodeList)args.get(1);
+            if (nodeList.getLength() > 0) {
+                return nodeList.item(0);
+            }
+        }
+        return null;
+    }
+
+    public Object evaluate(List args) throws XPathFunctionException {
+        if (logger.isLoggable(Level.FINE)) {
+            logger.fine(functionName + "(" + args + ")");
+        }
+
+        String arg = (String)args.get(0);
+        Node node = getContextNode(args);
+        /**
+         * If the xpath expression that contains the function does not select any nodes
+         * (eg IntentRefs('someIntent')), the context node passed in will be a Document. 
+         * In this case we need to iterate over every Node in the Document and evaluate it. 
+         * 
+         * If the xpath expression does select nodes (eg //sca:component[IntentRefs('someIntent')])
+         * then xpath will call evaluate for each node and we only need to return the result for that
+         * node.
+         */
+        if ( node instanceof Document ) 
+        	return evaluateDocument(arg, (Document)node);
+        else
+        	return evaluateNode(arg, node);
+    }
+    
+    public Object evaluateNode(String arg, Node node) {
+        if (InterfaceRef.equals(functionName)) {
+            return evaluateInterface(arg, node);
+        } else if (OperationRef.equals(functionName)) {
+            String[] params = arg.split("/");
+            if (params.length != 2) {
+                throw new IllegalArgumentException("Invalid argument: " + arg);
+            }
+            String interfaceName = params[0];
+            String operationName = params[1];
+            return evaluateOperation(interfaceName, operationName, node);
+        } else if (MessageRef.equals(functionName)) {
+            String[] params = arg.split("/");
+            if (params.length != 3) {
+                throw new IllegalArgumentException("Invalid argument: " + arg);
+            }
+            String interfaceName = params[0];
+            String operationName = params[1];
+            String messageName = params[2];
+            return evaluateMessage(interfaceName, operationName, messageName, node);
+        } else if (URIRef.equals(functionName)) {
+            return evaluateURI(arg, node);
+        } else if (IntentRefs.equals(functionName)) {
+            String[] intents = arg.split("(\\s)+");
+            return evaluateIntents(intents, node);
+        } else {
+            return Boolean.FALSE;
+        }
+    }
+
+    private class NodeListImpl implements NodeList {
+
+    	private ArrayList<Node> list;
+
+		public NodeListImpl() {
+    		this.list = new ArrayList<Node>();
+    	}
+		public int getLength() {
+			return this.list.size();
+		}
+
+		public Node item(int index) {			
+			return this.list.get(index);
+		}
+		public boolean add(Node node) {
+			return this.list.add(node);
+			
+		}
+    	
+    }
+    private Object evaluateDocument(String arg, Document doc) {
+    	NodeListImpl retList = new NodeListImpl();
+    	NodeList elements = doc.getElementsByTagName("*");
+		for ( int i=0; i < elements.getLength(); i++) {
+			Object node = evaluateNode(arg, elements.item(i));
+			if ( node != null ) 
+				retList.add((Node)node);
+		}
+		return retList;
+	}
+
+	private Boolean evaluateInterface(String interfaceName, Node node) {
+        return Boolean.FALSE;
+    }
+
+    private Boolean evaluateOperation(String interfaceName, String operationName, Node node) {
+        return Boolean.FALSE;
+    }
+
+    private Boolean evaluateMessage(String interfaceName, String operationName, String messageName, Node node) {
+        return Boolean.FALSE;
+    }
+
+    private Boolean evaluateURI(String uri, Node node) {
+        return Boolean.FALSE;
+    }
+
+    /**
+     * Evaluates a single node for the given intents. 
+     * @param intents
+     * @param node
+     * @return
+     */
+    private Object evaluateIntents(String[] intents, Node node) {
+    	if ( node == null ) 
+    		return false;
+    	    	
+    	if ( node.getAttributes() != null ) {
+    		for  ( int i=0; i < node.getAttributes().getLength(); i++) {
+    			Node attr = node.getAttributes().item(i);
+    			
+    			if ( "requires".equalsIgnoreCase(attr.getNodeName())) {
+    				
+    				for ( int j = 0; j < intents.length; j++ ) {
+    					// Check negative intents
+    					if ( intents[j].startsWith("!")) {
+    						if ( matchIntent(intents[j].substring(1), attr, node.getNamespaceURI()))
+    							return null; 
+    					} else if ( !matchIntent(intents[j], attr, node.getNamespaceURI())){
+    						return null; 
+    					}    					
+    				}
+    				return node; 
+    			}
+    			
+    		}
+    	}
+
+        return null; 
+    }
+
+    
+
+    /**
+     * Determine whether the given intent is present in the "requires" attribute
+     * @param intent
+     * @param node
+     * @param namespaceURI
+     * @return
+     */
+	private boolean matchIntent(String intent, Node node, String namespaceURI) {
+    	String[] requires = node.getNodeValue().split("(\\s)+");
+		QName intentName = getStringAsQName(intent);
+		
+		
+		for ( int i=0; i < requires.length; i++ ) {
+			QName nodeName = null;
+			int idx = requires[i].indexOf(':');
+			
+			// No prefix specified
+			if ( idx == -1 ) {
+				nodeName = new QName(namespaceURI, requires[i]);
+			} else {
+				String prefix = requires[i].substring(0, idx);
+				String name = requires[i].substring(idx + 1);
+				String ns = node.lookupNamespaceURI(prefix);
+				nodeName = new QName(ns, name, prefix);
+			}
+			if ( intentName.equals(nodeName))
+				return true;
+		}
+		return false;
+	}
+
+
+	private QName getStringAsQName(String intent) {
+		int idx = intent.indexOf(':');
+		if (idx == -1)
+			return new QName(namespaceContext.getNamespaceURI(XMLConstants.DEFAULT_NS_PREFIX), intent);
+		
+		String prefix = intent.substring(0, idx);
+		intent = intent.substring(idx + 1);
+		
+		return new QName(namespaceContext.getNamespaceURI(prefix), intent, prefix);
+		
+	}
+
+
+	private static Pattern FUNCTION;
+    static {
+        String functionPattern = "(URIRef|InterfaceRef|OperationRef|MessageRef|IntentRefs)\\s*\\(([^\\)]*)\\)";
+        FUNCTION = Pattern.compile(functionPattern);
+    }
+
+    /** Adds the node as an argument to the XPath function. 
+     * Required in order to have access to the NodeList within the function
+     */
+    public static String normalize(String attachTo, String scaPrefix) {
+    	// Get rid of any whitespace
+    	attachTo = attachTo.trim();
+    	
+        Matcher matcher = FUNCTION.matcher(attachTo);
+        boolean result = matcher.find();
+        if (result) {
+            StringBuffer sb = new StringBuffer();
+            do {
+                String function = matcher.group(1);
+                String args = matcher.group(2);
+                if ( (matcher.start() == 0) || (attachTo.charAt( matcher.start() -1) != ':' )) {
+                	function = scaPrefix + ":" + function; 
+                }
+                String replacement = null;
+                if (args.trim().length() > 0) {
+                    replacement = function + "(" + args + "," + "self::node())";
+                } else {
+                    replacement = function + "(self::node())";
+                }
+                matcher.appendReplacement(sb, replacement);
+                result = matcher.find();
+            } while (result);
+            
+            matcher.appendTail(sb);
+            return sb.toString();
+        }
+        return attachTo;
+    }
+
+}