com.bsiag.smartfield.server.services.lookup.CityLookupService.java Source code

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Here is the source code for com.bsiag.smartfield.server.services.lookup.CityLookupService.java

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/*******************************************************************************
 * Copyright (c) 2011 BSI AG.
 * All rights reserved. This program and the accompanying materials
 * are made available under the terms of the Eclipse Public License v1.0
 * which accompanies this distribution, and is available at
 * http://www.eclipse.org/legal/epl-v10.html
 * 
 * Contributors:
 *     Remo Arpagaus, BSI AG
 ******************************************************************************/
package com.bsiag.smartfield.server.services.lookup;

import java.io.File;
import java.io.IOException;
import java.util.ArrayList;
import java.util.List;

import org.apache.lucene.analysis.standard.StandardAnalyzer;
import org.apache.lucene.document.Document;
import org.apache.lucene.index.CorruptIndexException;
import org.apache.lucene.queryParser.MultiFieldQueryParser;
import org.apache.lucene.queryParser.QueryParser;
import org.apache.lucene.search.IndexSearcher;
import org.apache.lucene.search.Query;
import org.apache.lucene.search.ScoreDoc;
import org.apache.lucene.search.TopScoreDocCollector;
import org.apache.lucene.store.Directory;
import org.apache.lucene.store.SimpleFSDirectory;
import org.apache.lucene.util.Version;
import org.eclipse.scout.commons.BundleContextUtility;
import org.eclipse.scout.commons.exception.ProcessingException;
import org.eclipse.scout.commons.logger.IScoutLogger;
import org.eclipse.scout.commons.logger.ScoutLogManager;
import org.eclipse.scout.rt.server.services.lookup.AbstractLookupService;
import org.eclipse.scout.rt.shared.services.lookup.LookupCall;
import org.eclipse.scout.rt.shared.services.lookup.LookupRow;
import org.osgi.framework.ServiceRegistration;

import com.bsiag.smartfield.shared.services.lookup.ICityLookupService;

public class CityLookupService extends AbstractLookupService implements ICityLookupService {
    private static final IScoutLogger LOG = ScoutLogManager.getLogger(CityLookupService.class);

    private IndexSearcher searcher;
    private MultiFieldQueryParser byTextQueryParser;
    private QueryParser byKeyQueryParser;

    @Override
    public void initializeService(ServiceRegistration registration) {
        super.initializeService(registration);

        String path = BundleContextUtility.resolve("${workspace_loc}/com.bsiag.smartfield.server/resources/index");
        try {
            Directory index = new SimpleFSDirectory(new File(path));
            searcher = new IndexSearcher(index);

            byKeyQueryParser = new QueryParser(Version.LUCENE_34, "zip", new StandardAnalyzer(Version.LUCENE_34));
            byTextQueryParser = new MultiFieldQueryParser(Version.LUCENE_34, new String[] { "zip", "city" },
                    new StandardAnalyzer(Version.LUCENE_34));
            byTextQueryParser.setDefaultOperator(QueryParser.Operator.AND);
        } catch (IOException e) {
            LOG.error(e.getMessage(), e);
        }
    }

    public LookupRow[] getDataByKey(LookupCall call) throws ProcessingException {
        try {
            Query query = byKeyQueryParser.parse((String) call.getKey());
            return queryIndex(query, 1);
        } catch (Exception e) {
            LOG.error(e.getMessage(), e);
            throw new ProcessingException("Failed to query index");
        }
    }

    public LookupRow[] getDataByText(LookupCall call) throws ProcessingException {
        try {
            Query query = byTextQueryParser.parse(call.getText().replaceAll(" \\*", ""));
            return queryIndex(query, call.getMaxRowCount());
        } catch (Exception e) {
            LOG.error(e.getMessage(), e);
            throw new ProcessingException("Failed to query index");
        }
    }

    private LookupRow[] queryIndex(Query query, int maxRowCount) throws IOException, CorruptIndexException {
        TopScoreDocCollector collector = TopScoreDocCollector.create(maxRowCount, true);
        searcher.search(query, collector);
        ScoreDoc[] hits = collector.topDocs().scoreDocs;

        List<LookupRow> rows = new ArrayList<LookupRow>();
        for (int i = 0; i < hits.length; ++i) {
            int docId = hits[i].doc;
            Document d = searcher.doc(docId);
            String key = d.get("zip");
            String text = key + " " + d.get("city");
            rows.add(new LookupRow(key, text));
        }
        return rows.toArray(new LookupRow[rows.size()]);
    }

    public LookupRow[] getDataByAll(LookupCall call) throws ProcessingException {
        return new LookupRow[0];
    }

    public LookupRow[] getDataByRec(LookupCall call) throws ProcessingException {
        return new LookupRow[0];
    }
}