    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    }