Commons JXPath example source code file (JDOMNamespaceIterator.java)

This example Commons JXPath source code file (JDOMNamespaceIterator.java) is included in the DevDaily.com "Java Source Code Warehouse" project. The intent of this project is to help you "Learn Java by Example" ^TM.

Java - Commons JXPath tags/keywords

arraylist, document, document, element, jdomnamespaceiterator, jdomnamespaceiterator, list, namespace, namespace, nodeiterator, nodepointer, object, object, set, util

The Commons JXPath JDOMNamespaceIterator.java source code

/*
 * 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.commons.jxpath.ri.model.jdom;

import java.util.ArrayList;
import java.util.HashSet;
import java.util.List;
import java.util.Set;

import org.apache.commons.jxpath.ri.model.NodeIterator;
import org.apache.commons.jxpath.ri.model.NodePointer;
import org.jdom.Document;
import org.jdom.Element;
import org.jdom.Namespace;

/**
 * An iterator of namespaces of a DOM Node.
 *
 * @author Dmitri Plotnikov
 * @version $Revision: 652845 $ $Date: 2008-05-02 12:46:46 -0500 (Fri, 02 May 2008) $
 */
public class JDOMNamespaceIterator implements NodeIterator {
    private NodePointer parent;
    private List namespaces;
    private Set prefixes;
    private int position = 0;

    /**
     * Create a new JDOMNamespaceIterator.
     * @param parent the parent NodePointer.
     */
    public JDOMNamespaceIterator(NodePointer parent) {
        this.parent = parent;
        Object node = parent.getNode();
        if (node instanceof Document) {
            node = ((Document) node).getRootElement();
        }
        if (node instanceof Element) {
            namespaces = new ArrayList();
            prefixes = new HashSet();
            collectNamespaces((Element) node);
        }
    }

    /**
     * Collect the namespaces from a JDOM Element.
     * @param element the source Element
     */
    private void collectNamespaces(Element element) {
        Namespace ns = element.getNamespace();
        if (ns != null && !prefixes.contains(ns.getPrefix())) {
            namespaces.add(ns);
            prefixes.add(ns.getPrefix());
        }
        List others = element.getAdditionalNamespaces();
        for (int i = 0; i < others.size(); i++) {
            ns = (Namespace) others.get(i);
            if (ns != null && !prefixes.contains(ns.getPrefix())) {
                namespaces.add(ns);
                prefixes.add(ns.getPrefix());
            }
        }
        Object elementParent = element.getParent();
        if (elementParent instanceof Element) {
            collectNamespaces((Element) elementParent);
        }
    }

    public NodePointer getNodePointer() {
        if (position == 0) {
            if (!setPosition(1)) {
                return null;
            }
            position = 0;
        }
        int index = position - 1;
        if (index < 0) {
            index = 0;
        }
        Namespace ns = (Namespace) namespaces.get(index);
        return new JDOMNamespacePointer(parent, ns.getPrefix(), ns.getURI());
    }

    public int getPosition() {
        return position;
    }

    public boolean setPosition(int position) {
        if (namespaces == null) {
            return false;
        }
        this.position = position;
        return position >= 1 && position <= namespaces.size();
    }
}