com.celements.iterator.DocumentIterator.java Source code

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Here is the source code for com.celements.iterator.DocumentIterator.java

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/*
 * See the NOTICE file distributed with this work for additional
 * information regarding copyright ownership.
 *
 * This is free software; you can redistribute it and/or modify it
 * under the terms of the GNU Lesser General Public License as
 * published by the Free Software Foundation; either version 2.1 of
 * the License, or (at your option) any later version.
 *
 * This software is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
 * Lesser General Public License for more details.
 *
 * You should have received a copy of the GNU Lesser General Public
 * License along with this software; if not, write to the Free
 * Software Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA
 * 02110-1301 USA, or see the FSF site: http://www.fsf.org.
 */
package com.celements.iterator;

import java.util.ArrayList;
import java.util.Iterator;
import java.util.List;
import java.util.NoSuchElementException;

import org.apache.commons.logging.Log;
import org.apache.commons.logging.LogFactory;

import com.xpn.xwiki.XWiki;
import com.xpn.xwiki.XWikiContext;
import com.xpn.xwiki.XWikiException;
import com.xpn.xwiki.doc.XWikiDocument;

public class DocumentIterator implements Iterator<XWikiDocument>, Iterable<XWikiDocument> {

    private static Log mLogger = LogFactory.getFactory().getInstance(XObjectIterator.class);

    private List<String> _docList;
    private XWikiContext _context;
    private XWiki _xwiki;
    private Iterator<String> _docIterator;
    private XWikiDocument _currentDoc;

    /**
     * Constructor
     * @param XWiki context
     */
    public DocumentIterator(XWikiContext context) {
        _context = context;
        _xwiki = _context.getWiki();
    }

    /**
     * Checks if iterator has a next object
     */
    public boolean hasNext() {
        while ((_currentDoc == null) && (getDocIterator().hasNext())) {
            moveToNextDoc();
        }
        return (_currentDoc != null);
    }

    /**
     * Returns the next element in the iteration.
     *
     * @return the next element in the iteration.
     * @exception NoSuchElementException iteration has no more elements.
     */
    public XWikiDocument next() {
        if (hasNext()) {
            XWikiDocument theCurrentDoc = _currentDoc;
            _currentDoc = null;
            return theCurrentDoc;
        }
        throw new NoSuchElementException();
    }

    /**
     * Moves to the next document
     */
    void moveToNextDoc() {
        try {
            String fullname;
            do {
                fullname = getDocIterator().next();
            } while (!_xwiki.exists(fullname, _context) && getDocIterator().hasNext());
            if (_xwiki.exists(fullname, _context)) {
                _currentDoc = _xwiki.getDocument(fullname, _context);
            } else {
                _currentDoc = null;
            }
        } catch (XWikiException exp) {
            // If getDocument failed, getDocIterator still moved on by one document in list.
            // Hence the while loop in 'next' moves on to the next document in list.
            mLogger.error("Failed to get next xwiki document.", exp);
        }
    }

    /**
     * 
     * @return
     */
    Iterator<String> getDocIterator() {
        if (getDocList() == null) {
            throw new IllegalStateException("No doc list set.");
        }
        if (_docIterator == null) {
            _docIterator = getDocList().iterator();
        }
        return _docIterator;
    }

    /**
     * Gets the current document
     * @return current document
     */
    XWikiDocument getCurrentDoc() {
        if ((_currentDoc == null) && (getDocIterator().hasNext())) {
            moveToNextDoc();
        }
        return _currentDoc;
    }

    /**
     * FOR TESTS ONLY!!!
     * @param testCurrentDoc
     */
    void inject_CurrentDoc(XWikiDocument testCurrentDoc) {
        _currentDoc = testCurrentDoc;
    }

    /**
     * Remove is not supported
     * @throws UnsupportedOperationException
     */
    public void remove() {
        throw new UnsupportedOperationException();
    }

    /**
     * Set the document list
     * @param document list
     */
    public void setDocList(List<String> docList) {
        _docIterator = null;
        _docList = docList;
    }

    /**
     * Gets the document list
     * @return document list
     */
    List<String> getDocList() {
        return _docList;
    }

    /**
     * Get a copy of the document list
     * @return document list
     */
    public List<String> getDocListCopy() {
        return new ArrayList<String>(_docList);
    }

    public Iterator<XWikiDocument> iterator() {
        return this;
    }
}