001 /*
002 * Licensed to the Apache Software Foundation (ASF) under one or more
003 * contributor license agreements. See the NOTICE file distributed with
004 * this work for additional information regarding copyright ownership.
005 * The ASF licenses this file to You under the Apache License, Version 2.0
006 * (the "License"); you may not use this file except in compliance with
007 * the License. You may obtain a copy of the License at
008 *
009 * http://www.apache.org/licenses/LICENSE-2.0
010 *
011 * Unless required by applicable law or agreed to in writing, software
012 * distributed under the License is distributed on an "AS IS" BASIS,
013 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
014 * See the License for the specific language governing permissions and
015 * limitations under the License.
016 */
017 package org.apache.commons.jxpath.ri.axes;
018
019 import org.apache.commons.jxpath.ri.EvalContext;
020 import org.apache.commons.jxpath.ri.QName;
021 import org.apache.commons.jxpath.ri.compiler.NodeNameTest;
022 import org.apache.commons.jxpath.ri.compiler.NodeTest;
023 import org.apache.commons.jxpath.ri.model.NodeIterator;
024 import org.apache.commons.jxpath.ri.model.NodePointer;
025
026 /**
027 * EvalContext that walks the "namespace::" axis.
028 *
029 * @author Dmitri Plotnikov
030 * @version $Revision: 652845 $ $Date: 2008-05-02 12:46:46 -0500 (Fri, 02 May 2008) $
031 */
032 public class NamespaceContext extends EvalContext {
033 private NodeTest nodeTest;
034 private boolean setStarted = false;
035 private NodeIterator iterator;
036 private NodePointer currentNodePointer;
037
038 /**
039 * @param parentContext represents the previous step on the path
040 * @param nodeTest is the name of the namespace we are looking for
041 */
042 public NamespaceContext(EvalContext parentContext, NodeTest nodeTest) {
043 super(parentContext);
044 this.nodeTest = nodeTest;
045 }
046
047 public NodePointer getCurrentNodePointer() {
048 return currentNodePointer;
049 }
050
051 public void reset() {
052 setStarted = false;
053 iterator = null;
054 super.reset();
055 }
056
057 public boolean setPosition(int position) {
058 if (position < getCurrentPosition()) {
059 reset();
060 }
061
062 while (getCurrentPosition() < position) {
063 if (!nextNode()) {
064 return false;
065 }
066 }
067 return true;
068 }
069
070 public boolean nextNode() {
071 super.setPosition(getCurrentPosition() + 1);
072 if (!setStarted) {
073 setStarted = true;
074 if (!(nodeTest instanceof NodeNameTest)) {
075 return false;
076 }
077
078 NodeNameTest nodeNameTest = (NodeNameTest) nodeTest;
079 QName testName = nodeNameTest.getNodeName();
080 if (testName.getPrefix() != null) {
081 return false;
082 }
083 if (nodeNameTest.isWildcard()) {
084 iterator =
085 parentContext.getCurrentNodePointer().namespaceIterator();
086 }
087 else {
088 currentNodePointer =
089 parentContext.getCurrentNodePointer().namespacePointer(
090 testName.getName());
091 return currentNodePointer != null;
092 }
093 }
094
095 if (iterator == null) {
096 return false;
097 }
098 if (!iterator.setPosition(iterator.getPosition() + 1)) {
099 return false;
100 }
101 currentNodePointer = iterator.getNodePointer();
102 return true;
103 }
104 }