net.sourceforge.jwbf.actions.mw.queries.GetRecentchanges.java Source code

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Here is the source code for net.sourceforge.jwbf.actions.mw.queries.GetRecentchanges.java

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/*
 * Copyright 2007 Thomas Stock.
 * 
 * Licensed 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.
 * 
 * Contributors:
 * 
 */
package net.sourceforge.jwbf.actions.mw.queries;

import java.io.IOException;
import java.io.Reader;
import java.io.StringReader;
import java.util.ArrayList;
import java.util.Collection;
import java.util.Iterator;

import net.sourceforge.jwbf.actions.mw.MultiAction;
import net.sourceforge.jwbf.actions.mw.util.MWAction;
import net.sourceforge.jwbf.actions.mw.util.ProcessException;

import org.apache.commons.httpclient.methods.GetMethod;
import org.jdom.Document;
import org.jdom.Element;
import org.jdom.JDOMException;
import org.jdom.input.SAXBuilder;
import org.xml.sax.InputSource;

/**
 * 
 * Gets a list of pages recently changed, ordered by modification timestamp.
 * Parameters: rcfrom (paging timestamp), rcto (flt), rcnamespace (flt), rcminor
 * (flt), rcusertype (dflt=not|bot), rcdirection (dflt=older), rclimit (dflt=10,
 * max=500/5000) F
 * 
 * api.php ? action=query & list=recentchanges - List last 10 changes
    
 * @author Thomas Stock
 * @supportedBy MediaWikiAPI 1.10 recentchanges / rc
 */

public class GetRecentchanges extends MWAction implements MultiAction<String> {

    /** value for the bllimit-parameter. **/
    private int limit = 10;

    /**
     * Collection that will contain the result
     * (titles of articles linking to the target) 
     * after performing the action has finished.
     */
    private Collection<String> titleCollection = new ArrayList<String>();

    /**
     * information necessary to get the next api page.
     */

    /**
     * generates the next MediaWiki-request (GetMethod) and adds it to msgs.
     * @param namespace     the namespace(s) that will be searched for links,
     *                      as a string of numbers separated by '|';
     *                      if null, this parameter is omitted
     */
    protected void generateRequest(String namespace) {

        String uS = "";

        uS = "/api.php?action=query&list=recentchanges"

                + ((namespace != null) ? ("&rcnamespace=" + namespace) : "")
                //+ "&rcminor="
                //+ "&rcusertype=" // (dflt=not|bot)
                + "&rclimit=" + limit + "&format=xml";

        msgs.add(new GetMethod(uS));

    }

    /**
     * 
     */
    public GetRecentchanges(String ns) {
        generateRequest(ns);
    }

    /**
     * 
     */
    public GetRecentchanges(int count, String ns) {
        this.limit = count;
        generateRequest(ns);
    }

    /**
     * deals with the MediaWiki api's response by parsing the provided text.
     *
     * @param s   the answer to the most recently generated MediaWiki-request
     *
     * @return empty string
     */
    public String processAllReturningText(final String s) throws ProcessException {
        String t = s;
        parseArticleTitles(t);

        return "";
    }

    /**
     * picks the article name from a MediaWiki api response.
     *   
     * @param s   text for parsing
     */
    public void parseArticleTitles(String s) {

        SAXBuilder builder = new SAXBuilder();
        Element root = null;
        try {
            Reader i = new StringReader(s);
            Document doc = builder.build(new InputSource(i));

            root = doc.getRootElement();

        } catch (JDOMException e) {
            // TODO Auto-generated catch block
            e.printStackTrace();
        } catch (IOException e) {
            // TODO Auto-generated catch block
            e.printStackTrace();
        }
        findContent(root);

    }

    @SuppressWarnings("unchecked")
    private void findContent(final Element root) {

        Iterator<Element> el = root.getChildren().iterator();
        while (el.hasNext()) {
            Element element = (Element) el.next();
            if (element.getQualifiedName().equalsIgnoreCase("rc")) {

                titleCollection.add(element.getAttributeValue("title"));

            } else {
                findContent(element);
            }

        }
    }

    /**
     * @return   the collected article names
     */
    public Collection<String> getResults() {
        return titleCollection;
    }

    /**
     * @return   necessary information for the next action
     *           or null if no next api page exists
     */
    public GetRecentchanges getNextAction() {
        return null;
    }

}