eu.sisob.uma.NPL.Researchers.Freebase.Utils.java Source code

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Here is the source code for eu.sisob.uma.NPL.Researchers.Freebase.Utils.java

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/*
Copyright (c) 2014 "(IA)2 Research Group. Universidad de Mlaga"
                    http://iaia.lcc.uma.es | http://www.uma.es
This file is part of SISOB Data Extractor.
SISOB Data Extractor 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.
SISOB Data Extractor 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 SISOB Data Extractor. If not, see <http://www.gnu.org/licenses/>.
*/

package eu.sisob.uma.NPL.Researchers.Freebase;

import com.google.gson.JsonArray;
import com.google.gson.JsonObject;
import com.google.gson.JsonParser;
import java.io.IOException;
import java.io.UnsupportedEncodingException;
import java.net.URLEncoder;
import java.util.ArrayList;
import java.util.Iterator;
import java.util.List;
import org.apache.http.HttpResponse;
import org.apache.http.client.HttpClient;
import org.apache.http.client.methods.HttpGet;
import org.apache.http.impl.client.DefaultHttpClient;
import org.apache.http.util.EntityUtils;
import org.apache.log4j.Logger;

/**
 *
 * @author Daniel Lpez Gonzlez (dlopezgonzalez@gmail.com) for the SISOB PROJECT (http://sisob.lcc.uma.es/)
 */
public class Utils {

    /*
     * Return JsonObject of a REST call of url
     * 
     * @param url   
     * @return  JsonObject of the result
     * @throws IOException
     */
    public static JsonObject doRESTCall(String url) throws IOException {
        HttpClient httpclient = new DefaultHttpClient();
        HttpResponse response = httpclient.execute(new HttpGet(url));

        JsonParser parser = new JsonParser();
        JsonObject json_data = (JsonObject) parser.parse(EntityUtils.toString(response.getEntity()));

        return json_data;
    }

    /*
     * Get the results JsonArray of Freebase API Search Call   
     * 
     * @param query     query
     * @param key       API key
     * @param params        extra params to be added to the call
     * @return
     */
    public static JsonArray getResultsFromAPISearchCall(String query, String key, String params) {
        String service_url = "https://www.googleapis.com/freebase/v1/search";
        String url = "";
        JsonObject json_data = null;
        try {
            url = service_url + "?query=" + URLEncoder.encode(query, "UTF-8") + params + "&key=" + key + "&limit=1";

            json_data = doRESTCall(url);
        } catch (UnsupportedEncodingException ex) {
            ProjectLogger.LOGGER.error(ex.getMessage());
            json_data = null;
        } catch (IOException ex) {
            ProjectLogger.LOGGER.error(ex.getMessage());
            json_data = null;
        }

        JsonArray results = null;
        if (json_data != null) {
            results = (JsonArray) json_data.get("result");
        }

        return results;
    }

    /**
     * Get canonical name in Freebase of expression given 
     * @param expression
     * @param key
     * @param params        extra params to be added to the call
     * @return
     * @throws IOException
     */
    public static String[] getCanonicalInfoFromEntity(String expression, String key, String params) {
        JsonArray results = getResultsFromAPISearchCall(expression, key, params);
        String[] info = new String[2];
        if (results != null) {
            for (Object planet : results) {
                info[0] = ((JsonObject) planet).get("name").getAsJsonPrimitive().getAsString();
                info[1] = ((JsonObject) planet).get("mid").getAsJsonPrimitive().getAsString();
                break;
            }
        }

        return info;
    }

    /**
     * Get entity mid in Freebase of expression given 
     * @param expression
     * @param key
     * @param params        extra params to be added to the call
     * @return
     * @throws IOException
     */
    //    public static String getCanonicalMidFromEntity(String expression, String key, String params)
    //    {   
    //        JsonArray results = getResultsFromAPISearchCall(expression, key, params);
    //        String name = "";
    //        if(results != null)
    //        {
    //            for (Object planet : results) 
    //            {
    //                name = ((JsonObject)planet).get("mid").getAsJsonPrimitive().getAsString();
    //                break;
    //            }
    //        }      
    //
    //        return name;        
    //    }

    /**
    * Get the results JsonArray of Freebase MQL Read API call
    * 
    * @param query
    * @return
    */
    public static JsonArray getResultsFromMQLReadCall(String query) {
        String service_url = "https://www.googleapis.com/freebase/v1/mqlread";
        String url;
        JsonObject json_data = null;
        try {
            url = service_url + "?query=" + URLEncoder.encode(query, "UTF-8")
                    + "&key=AIzaSyBwYBI9bKtHDKRLfCjCx1p78-zsbGldD7Y";
            json_data = doRESTCall(url);
        } catch (UnsupportedEncodingException ex) {
            ProjectLogger.LOGGER.error(ex.getMessage());
            json_data = null;
        } catch (IOException ex) {
            ProjectLogger.LOGGER.error(ex.getMessage());
            json_data = null;
        }

        JsonArray results = null;
        if (json_data != null) {
            results = (JsonArray) json_data.get("result");
        }

        return results;
    }
}