    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.model.jdom;
    019
    020import java.util.ArrayList;
    021import java.util.HashSet;
    022import java.util.List;
    023import java.util.Set;
    024
    025import org.apache.commons.jxpath.ri.model.NodeIterator;
    026import org.apache.commons.jxpath.ri.model.NodePointer;
    027import org.jdom.Document;
    028import org.jdom.Element;
    029import org.jdom.Namespace;
    030
    031/**
    032 * An iterator of namespaces of a DOM Node.
    033 */
    034public class JDOMNamespaceIterator implements NodeIterator {
    035
    036    private final NodePointer parent;
    037    private List<Namespace> namespaces;
    038    private Set<String> prefixes;
    039    private int position;
    040
    041    /**
    042     * Constructs a new JDOMNamespaceIterator.
    043     *
    044     * @param parent the parent NodePointer.
    045     */
    046    public JDOMNamespaceIterator(final NodePointer parent) {
    047        this.parent = parent;
    048        Object node = parent.getNode();
    049        if (node instanceof Document) {
    050            node = ((Document) node).getRootElement();
    051        }
    052        if (node instanceof Element) {
    053            namespaces = new ArrayList<>();
    054            prefixes = new HashSet<>();
    055            collectNamespaces((Element) node);
    056        }
    057    }
    058
    059    /**
    060     * Collect the namespaces from a JDOM Element.
    061     *
    062     * @param element the source Element
    063     */
    064    private void collectNamespaces(final Element element) {
    065        Namespace ns = element.getNamespace();
    066        if (ns != null && !prefixes.contains(ns.getPrefix())) {
    067            namespaces.add(ns);
    068            prefixes.add(ns.getPrefix());
    069        }
    070        final List others = element.getAdditionalNamespaces();
    071        for (final Object other : others) {
    072            ns = (Namespace) other;
    073            if (ns != null && !prefixes.contains(ns.getPrefix())) {
    074                namespaces.add(ns);
    075                prefixes.add(ns.getPrefix());
    076            }
    077        }
    078        final Object elementParent = element.getParent();
    079        if (elementParent instanceof Element) {
    080            collectNamespaces((Element) elementParent);
    081        }
    082    }
    083
    084    @Override
    085    public NodePointer getNodePointer() {
    086        if (position == 0) {
    087            if (!setPosition(1)) {
    088                return null;
    089            }
    090            position = 0;
    091        }
    092        int index = position - 1;
    093        if (index < 0) {
    094            index = 0;
    095        }
    096        final Namespace ns = namespaces.get(index);
    097        return new JDOMNamespacePointer(parent, ns.getPrefix(), ns.getURI());
    098    }
    099
    100    @Override
    101    public int getPosition() {
    102        return position;
    103    }
    104
    105    @Override
    106    public boolean setPosition(final int position) {
    107        if (namespaces == null) {
    108            return false;
    109        }
    110        this.position = position;
    111        return position >= 1 && position <= namespaces.size();
    112    }
    113}