edu.txstate.dmlab.clusteringwiki.sources.AbsSearcher.java Source code

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Here is the source code for edu.txstate.dmlab.clusteringwiki.sources.AbsSearcher.java

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package edu.txstate.dmlab.clusteringwiki.sources;

/**
 *  ClusteringWiki - personalized and collaborative clustering of search results
 *  Copyright (C) 2010  Texas State University-San Marcos
 *  
 *  Contact: http://dmlab.cs.txstate.edu
 * 
 *  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 3 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, see <http://www.gnu.org/licenses/>.
 */

import java.io.IOException;
import java.io.UnsupportedEncodingException;
import java.net.MalformedURLException;

import javax.servlet.http.HttpServletRequest;

import org.json.JSONException;
import org.json.JSONObject;
import org.springframework.beans.factory.annotation.Autowired;

import edu.txstate.dmlab.clusteringwiki.util.URLUtils;

/**
 * Abstract searcher implementation
 * 
 * @author David C. Anastasiu
 *
 */
public class AbsSearcher extends BaseCWSearcher implements ICWSearcher {

    /**
     * API URL path without domain if localDomain is true
     */
    private static final String baseUrlPath = "AbstractSearch/rest/search/";

    @Autowired(required = true)
    private HttpServletRequest httpRequest;

    /**
     * Search data source key
     */
    protected String key = "abs";

    /**
     * Search data source name/label
     */
    protected String label = "AbS Search API";

    /**
     * Default constructor
     */
    public AbsSearcher() {

    }

    /**
     * Practical implementation of the search method
     */
    public ICWSearchResultCol search(String service, String query, int start, int count) {

        AbsSearchResultCol col = null;

        if (baseUrlPath == null || baseUrlPath.length() < 10) {
            if (col == null)
                col = new AbsSearchResultCol(null);
            col.addError("Error calling AbS Search Service: invalid baseUrlPath.");
            return col;
        }

        //query specifics
        if (start < 1)
            start = 1;
        if (count < 0)
            count = getNumResults();

        //build service query
        String url = null;
        try {
            url = buildRequestUrl(service, query, start, count);
        } catch (UnsupportedEncodingException e) {
            if (col == null)
                col = new AbsSearchResultCol(null);
            col.addError("Error calling AbS Search Service: invalid query string.");
            return col;
        }

        //execute query
        try {

            String doc = URLUtils.getWebPage(url);
            JSONObject res = new JSONObject(doc);

            col = new AbsSearchResultCol(res);
            col.setDataSourceInfo(key, label);
            col.setFirstPosition(start);

        } catch (JSONException e) {
            if (col == null)
                col = new AbsSearchResultCol(null);
            col.addError("Error calling AbS Search Service: " + e.toString());
            return col;
        } catch (MalformedURLException e) {
            if (col == null)
                col = new AbsSearchResultCol(null);
            col.addError("Error calling AbS Search Service: " + e.toString());
            return col;
        } catch (IOException e) {
            // Most likely a network exception of some sort.
            if (col == null)
                col = new AbsSearchResultCol(null);
            col.addError("Error calling AbS Search Service: " + e.toString());
            return col;
        }

        return col;
    }

    /**
     * Build the request URL string in the correct format expected 
     * by the AbS Search API
     */
    private String buildRequestUrl(String service, String query, int start, int count)
            throws UnsupportedEncodingException {
        //build base URL
        String url = "";

        if (!baseUrlPath.toLowerCase().startsWith("http")) {
            String q[] = httpRequest.getRequestURL().toString().split("\\/");
            if (baseUrlPath.startsWith("/") || baseUrlPath.startsWith("\\"))
                url = q[0] + "//" + q[2] + "/" + baseUrlPath.substring(1);
            else
                url = q[0] + "//" + q[2] + "/" + baseUrlPath;
        } else {
            url = baseUrlPath;
        }

        if (baseUrlPath.endsWith("/") || baseUrlPath.endsWith("\\"))
            url = url.substring(0, url.length() - 1);

        //add query specifics
        url += "/" + service + "/" + java.net.URLEncoder.encode(query, "UTF-8") + "/" + count + "/" + start
                + ".json";

        return url;
    }

}