es.gva.cit.gazetteer.adl.protocols.ADLThesaurus.java Source code

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Here is the source code for es.gva.cit.gazetteer.adl.protocols.ADLThesaurus.java

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/* gvSIG. Sistema de Informacin Geogrfica de la Generalitat Valenciana
 *
 * Copyright (C) 2004 IVER T.I. and Generalitat Valenciana.
 *
 * This program is free software; you can redistribute it and/or
 * modify it under the terms of the GNU General Public License
 * as published by the Free Software Foundation; either version 2
 * of the License, or (at your option) any later version.
 *
 * This program 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 General Public License for more details.
 *
 * You should have received a copy of the GNU General Public License
 * along with this program; if not, write to the Free Software
 * Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA  02111-1307,USA.
 *
 * For more information, contact:
 *
 *  Generalitat Valenciana
 *   Conselleria d'Infraestructures i Transport
 *   Av. Blasco Ibez, 50
 *   46010 VALENCIA
 *   SPAIN
 *
 *      +34 963862235
 *   gvsig@gva.es
 *      www.gvsig.gva.es
 *
 *    or
 *
 *   IVER T.I. S.A
 *   Salamanca 50
 *   46005 Valencia
 *   Spain
 *
 *   +34 963163400
 *   dac@iver.es
 */
package es.gva.cit.gazetteer.adl.protocols;

import java.net.MalformedURLException;
import java.net.URL;
import java.util.Collection;

import org.apache.commons.httpclient.NameValuePair;

import es.gva.cit.catalog.metadataxml.XMLNode;
import es.gva.cit.catalog.metadataxml.XMLTree;
import es.gva.cit.catalog.protocols.HTTPGetProtocol;
import es.gva.cit.gazetteer.querys.FeatureType;

/**
 * This class implemets an ADL thesaurus client
 * 
 * @author Jorge Piera Llodra (piera_jor@gva.es)
 * @see http://middleware.alexandria.ucsb.edu:8080/thes/FTT/index.html
 */
public class ADLThesaurus {
    private URL url;
    private FeatureType[] features;

    public ADLThesaurus(URL url) {
        setUrl(url);
        getNarrower();
    }

    /**
     * It implements the getNarrower ADL thesaurus operation
     * 
     */
    private void getNarrower() {
        URL urlNarrower;
        try {
            urlNarrower = new URL("http", getUrl().getHost(), getUrl().getPort(),
                    getUrl().getFile() + "/get-narrower");
        } catch (MalformedURLException e) {
            // TODO Auto-generated catch block
            e.printStackTrace();
            return;
        }
        Collection nodes = new HTTPGetProtocol().doQuery(urlNarrower, getNarrowerParams(), 0);
        parseGetNarrowAnswer((XMLNode) nodes.toArray()[0]);
    }

    /**
     * It returns the name-value pair for the getNarrower opertaion
     * 
     * @return Name-value pair
     */
    private NameValuePair[] getNarrowerParams() {
        String message = "";
        System.out.println(message);
        NameValuePair nvp1 = new NameValuePair("starting-term", "");
        NameValuePair nvp2 = new NameValuePair("max-levels", "-1");
        NameValuePair nvp3 = new NameValuePair("format", "term");

        return new NameValuePair[] { nvp1, nvp2, nvp3 };
    }

    /**
     * It parses the getNarrow answer into a Feature arrray
     * 
     * @param node
     */
    private void parseGetNarrowAnswer(XMLNode node) {
        XMLNode[] rootNodes = XMLTree.searchMultipleNode(node, "hierarchy->node->node");
        FeatureType[] features = new FeatureType[rootNodes.length];
        for (int i = 0; i < rootNodes.length; i++) {
            FeatureType thesaurus = new FeatureType(XMLTree.searchNodeValue(rootNodes[i], "term"));
            thesaurus.setFeatures(parseRecursiveFeatures(rootNodes[i], thesaurus));
            thesaurus.setTitle(thesaurus.getName());
            features[i] = (thesaurus);
        }
        setFeatures(features);
    }

    /**
     * It is used to parse a feature using recursivity.
     * 
     * @return
     * @param node
     *            Feature tree
     * @param thesaurus
     *            Feature to add the child Features
     */
    private FeatureType[] parseRecursiveFeatures(XMLNode node, FeatureType thesaurus) {
        XMLNode[] rootNodes = XMLTree.searchMultipleNode(node, "node");

        if ((rootNodes == null) || (rootNodes.length == 0)) {
            return null;
        }

        FeatureType[] features = new FeatureType[rootNodes.length];
        for (int i = 0; i < rootNodes.length; i++) {
            FeatureType f = new FeatureType(XMLTree.searchNodeValue(rootNodes[i], "term"));
            f.setTitle(f.getName());
            f.setFeatures(parseRecursiveFeatures(rootNodes[i], f));
            features[i] = f;
        }
        return features;
    }

    /**
     * @return Returns the url.
     */
    public URL getUrl() {
        return url;
    }

    /**
     * @param url
     *            The url to set.
     */
    public void setUrl(URL url) {
        this.url = url;
    }

    /**
     * @return Returns the features.
     */
    public FeatureType[] getFeatures() {
        return features;
    }

    /**
     * @param features
     *            The features to set.
     */
    public void setFeatures(FeatureType[] features) {
        this.features = features;
    }
}