eu.europeana.suggest.QueryCompletionClient.java Source code

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Here is the source code for eu.europeana.suggest.QueryCompletionClient.java

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/**
 *  Copyright 2014 Diego Ceccarelli
 *
 *  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.
 */
package eu.europeana.suggest;

import java.io.UnsupportedEncodingException;
import java.util.ArrayList;
import java.util.List;

import org.apache.solr.client.solrj.SolrQuery;
import org.apache.solr.client.solrj.SolrServerException;
import org.apache.solr.client.solrj.impl.HttpSolrServer;
import org.apache.solr.client.solrj.response.QueryResponse;
import org.apache.solr.common.SolrDocument;
import org.apache.solr.common.SolrDocumentList;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;

/**
 * @author Diego Ceccarelli <diego.ceccarelli@isti.cnr.it>
 * 
 *         Created on Dec 6, 2014
 */
public class QueryCompletionClient {

    public String serverUrl = "http://localhost:8080";
    private final String[] languages = new String[] { "it", "de", "fr" };

    private static final Logger logger = LoggerFactory.getLogger(QueryCompletionClient.class);

    private final HttpSolrServer server;

    public QueryCompletionClient() {
        String uri = System.getenv("server");
        if (uri != null) {
            serverUrl = uri;
        }
        serverUrl += "/europeana";
        server = new HttpSolrServer(serverUrl);

    }

    public Response getCompletions(String query, int n, String language) throws SolrServerException {
        return getCompletions(query, n, language, false);
    }

    public Response getCompletions(String query, int n, String language, boolean addExplain)
            throws SolrServerException {

        if (language == null || language.isEmpty()) {
            logger.info("no language for query {}, using default English. ", language, query);
            return getCompletions(query, n);
        }

        language = language.toLowerCase();

        if (!language.contains(language)) {
            logger.info("unknown language {} for query {}, using default English. ", language, query);
            language = "en";
        }

        SolrQuery sq = new SolrQuery(query);
        if (language.equals("en")) {
            sq.setRequestHandler("/suggest");
        } else {
            sq.setRequestHandler("/" + language + "_suggest");
        }
        // set the results number
        sq.setRows(n);
        if (addExplain) {
            // if requested add the explain (how the score is computed) to the
            // results, used in the logging
            sq.setFields("*", "[explain]");
        }
        // send the query to the server, each document returned is an entity
        QueryResponse qr = server.query(sq);
        SolrDocumentList sdl = qr.getResults();

        Response result = new Response(query);

        result.setItemCount(n);
        result.setTotalResults(sdl.getNumFound());
        result.setLanguage(language);

        List<Suggestion> annotations = new ArrayList<Suggestion>();
        for (SolrDocument sd : sdl) {
            Suggestion annotation = new Suggestion();
            String enTitle = (decode((String) sd.get("en_title")));
            // short titles usually are not really relevant and have high
            // ranking since they are ambigous.. remove them :)
            if (enTitle.length() <= 5)
                continue;
            int wikipediaClicks = ((Integer) sd.get("wikipedia_clicks"));
            int europeanaDf = ((Integer) sd.get("europeana_df"));
            int enrichment = ((Integer) sd.get("enrichment"));
            String type = (decode((String) sd.get("type"))).toLowerCase();
            annotation.setType(type);
            annotation.addPrefLabel("en", enTitle);
            annotation.setEuropeana_df(europeanaDf);
            annotation.setWikipedia_clicks(wikipediaClicks);
            annotation.setEnrichment(enrichment);
            if (addExplain) {
                annotation.setExplain((String) sd.get("[explain]"));
            }

            for (String lang : languages) {
                String label = decode((String) sd.get(lang + "_title"));

                if (label == null || label.isEmpty())
                    continue;
                // if (label == null || label.isEmpty()) {
                // label = enTitle;
                //
                // }
                annotation.addPrefLabel(lang, label);
            }
            annotation.setUri((String) sd.get("uri"));
            annotation.setImage(((String) sd.get("uri")).replace("http://dbpedia.org/resource/",
                    "http://wikiname2image.herokuapp.com/"));
            annotation.setUri(annotation.getUri().replace("http://dbpedia.org/resource/",
                    "http://data.europeana.eu/" + type + "/"));
            annotation.setSearch("entity:" + annotation.getUri());
            annotations.add(annotation);
        }
        result.setSuggestions(annotations);

        return result;

    }

    public Response getCompletions(String query, int n) throws SolrServerException {

        return getCompletions(query, n, "en");

    }

    private String decode(String string) {
        try {
            return java.net.URLDecoder.decode(string, "UTF-8");
        } catch (UnsupportedEncodingException e) {
            return string;
        }
    }

    public static void main(String[] args) throws SolrServerException {
        QueryCompletionClient qcc = new QueryCompletionClient();
        Response sugg = qcc.getCompletions("leonard da vinci", 10, "fr");
        for (Suggestion ann : sugg.getSuggestions()) {
            System.out.println(ann.getPrefLabel());
        }
    }
}