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
018package org.apache.commons.jxpath.ri.axes;
019
020import org.apache.commons.jxpath.ri.EvalContext;
021import org.apache.commons.jxpath.ri.QName;
022import org.apache.commons.jxpath.ri.compiler.NodeNameTest;
023import org.apache.commons.jxpath.ri.compiler.NodeTest;
024import org.apache.commons.jxpath.ri.model.NodeIterator;
025import org.apache.commons.jxpath.ri.model.NodePointer;
026
027/**
028 * EvalContext that walks the "namespace::" axis.
029 */
030public class NamespaceContext extends EvalContext {
031
032    private final NodeTest nodeTest;
033    private boolean setStarted;
034    private NodeIterator iterator;
035    private NodePointer currentNodePointer;
036
037    /**
038     * Constructs a new instance.
039     *
040     * @param parentContext represents the previous step on the path
041     * @param nodeTest      is the name of the namespace we are looking for
042     */
043    public NamespaceContext(final EvalContext parentContext, final NodeTest nodeTest) {
044        super(parentContext);
045        this.nodeTest = nodeTest;
046    }
047
048    @Override
049    public NodePointer getCurrentNodePointer() {
050        return currentNodePointer;
051    }
052
053    @Override
054    public boolean nextNode() {
055        super.setPosition(getCurrentPosition() + 1);
056        if (!setStarted) {
057            setStarted = true;
058            if (!(nodeTest instanceof NodeNameTest)) {
059                return false;
060            }
061            final NodeNameTest nodeNameTest = (NodeNameTest) nodeTest;
062            final QName testName = nodeNameTest.getNodeName();
063            if (testName.getPrefix() != null) {
064                return false;
065            }
066            if (!nodeNameTest.isWildcard()) {
067                currentNodePointer = parentContext.getCurrentNodePointer().namespacePointer(testName.getName());
068                return currentNodePointer != null;
069            }
070            iterator = parentContext.getCurrentNodePointer().namespaceIterator();
071        }
072        if (iterator == null) {
073            return false;
074        }
075        if (!iterator.setPosition(iterator.getPosition() + 1)) {
076            return false;
077        }
078        currentNodePointer = iterator.getNodePointer();
079        return true;
080    }
081
082    @Override
083    public void reset() {
084        setStarted = false;
085        iterator = null;
086        super.reset();
087    }
088
089    @Override
090    public boolean setPosition(final int position) {
091        if (position < getCurrentPosition()) {
092            reset();
093        }
094        while (getCurrentPosition() < position) {
095            if (!nextNode()) {
096                return false;
097            }
098        }
099        return true;
100    }
101}