org.sindice.siren.demo.SimpleIndexer.java Source code

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Here is the source code for org.sindice.siren.demo.SimpleIndexer.java

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/**
 * Copyright 2014 National University of Ireland, Galway.
 *
 * This file is part of the SIREn project. Project and contact information:
 *
 *  https://github.com/rdelbru/SIREn
 *
 * 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 org.sindice.siren.demo;

import java.io.File;
import java.io.IOException;
import java.io.Reader;

import org.apache.lucene.analysis.Analyzer;
import org.apache.lucene.analysis.TokenStream;
import org.apache.lucene.analysis.core.LowerCaseFilter;
import org.apache.lucene.analysis.standard.StandardAnalyzer;
import org.apache.lucene.codecs.Codec;
import org.apache.lucene.codecs.PostingsFormat;
import org.apache.lucene.codecs.lucene40.Lucene40Codec;
import org.apache.lucene.codecs.lucene40.Lucene40PostingsFormat;
import org.apache.lucene.document.Document;
import org.apache.lucene.document.Field;
import org.apache.lucene.document.Field.Store;
import org.apache.lucene.document.FieldType;
import org.apache.lucene.document.StringField;
import org.apache.lucene.index.IndexWriter;
import org.apache.lucene.index.IndexWriterConfig;
import org.apache.lucene.store.Directory;
import org.apache.lucene.store.FSDirectory;
import org.apache.lucene.util.Version;
import org.sindice.siren.analysis.JsonTokenizer;
import org.sindice.siren.analysis.filter.DatatypeAnalyzerFilter;
import org.sindice.siren.analysis.filter.PositionAttributeFilter;
import org.sindice.siren.analysis.filter.SirenPayloadFilter;
import org.sindice.siren.index.codecs.siren10.Siren10AForPostingsFormat;

/**
 * This class shows how to configure the SIREn codec for indexing JSON data
 * into a particular field.
 */
public class SimpleIndexer {

    private final Directory dir;
    private final IndexWriter writer;

    public static final String DEFAULT_ID_FIELD = "id";
    public static final String DEFAULT_SIREN_FIELD = "siren-field";

    public SimpleIndexer(final File path) throws IOException {
        dir = FSDirectory.open(path);
        writer = this.initializeIndexWriter();
    }

    public void close() throws IOException {
        writer.close();
        dir.close();
    }

    private IndexWriter initializeIndexWriter() throws IOException {
        final IndexWriterConfig config = new IndexWriterConfig(Version.LUCENE_40, this.initializeAnalyzer());

        // Register the SIREn codec
        config.setCodec(new Siren10Codec());

        return new IndexWriter(dir, config);
    }

    private Analyzer initializeAnalyzer() {
        return new Analyzer() {

            @Override
            protected TokenStreamComponents createComponents(final String fieldName, final Reader reader) {
                final Version matchVersion = Version.LUCENE_40;
                final JsonTokenizer src = new JsonTokenizer(reader);
                TokenStream tok = new DatatypeAnalyzerFilter(matchVersion, src, new StandardAnalyzer(matchVersion),
                        new StandardAnalyzer(matchVersion));
                tok = new LowerCaseFilter(matchVersion, tok);
                // The PositionAttributeFilter and SirenPayloadFilter are mandatory
                // and must be always the last filters in your token stream
                tok = new PositionAttributeFilter(tok);
                tok = new SirenPayloadFilter(tok);
                return new TokenStreamComponents(src, tok);
            }

        };
    }

    public void addDocument(final String id, final String json) throws IOException {
        final Document doc = new Document();

        doc.add(new StringField(DEFAULT_ID_FIELD, id, Store.YES));

        final FieldType sirenFieldType = new FieldType();
        sirenFieldType.setIndexed(true);
        sirenFieldType.setTokenized(true);
        sirenFieldType.setOmitNorms(true);
        sirenFieldType.setStored(false);
        sirenFieldType.setStoreTermVectors(false);

        doc.add(new Field(DEFAULT_SIREN_FIELD, json, sirenFieldType));

        writer.addDocument(doc);
    }

    public void commit() throws IOException {
        writer.commit();
    }

    /**
     * Simple example of a SIREn codec that will use the SIREn posting format
     * for a given field.
     */
    private class Siren10Codec extends Lucene40Codec {

        final PostingsFormat lucene40 = new Lucene40PostingsFormat();
        PostingsFormat defaultTestFormat = new Siren10AForPostingsFormat();

        public Siren10Codec() {
            Codec.setDefault(this);
        }

        @Override
        public PostingsFormat getPostingsFormatForField(final String field) {
            if (field.equals(DEFAULT_SIREN_FIELD)) {
                return defaultTestFormat;
            } else {
                return lucene40;
            }
        }

        @Override
        public String toString() {
            return "Siren10Codec[" + defaultTestFormat.toString() + "]";
        }

    }

}