org.apache.nutch.searcher.LuceneSearchBean.java Source code

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Here is the source code for org.apache.nutch.searcher.LuceneSearchBean.java

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/**
 * Licensed to the Apache Software Foundation (ASF) under one or more
 * contributor license agreements.  See the NOTICE file distributed with
 * this work for additional information regarding copyright ownership.
 * The ASF licenses this file to You 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.apache.nutch.searcher;

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

import org.apache.hadoop.conf.Configuration;
import org.apache.hadoop.fs.FileStatus;
import org.apache.hadoop.fs.FileSystem;
import org.apache.hadoop.fs.Path;
import org.apache.nutch.indexer.Indexer;
import org.apache.nutch.util.HadoopFSUtil;

public class LuceneSearchBean implements RPCSearchBean {

    public static final long VERSION = 1L;

    private IndexSearcher searcher;

    private FileSystem fs;

    private Configuration conf;

    /**
     * Construct in a named directory.
     * @param conf
     * @param dir
     * @throws IOException
     */
    public LuceneSearchBean(Configuration conf, Path indexDir, Path indexesDir) throws IOException {
        this.conf = conf;
        this.fs = FileSystem.get(this.conf);
        init(indexDir, indexesDir);
    }

    private void init(Path indexDir, Path indexesDir) throws IOException {
        Path absIndexDir = indexDir.makeQualified(indexDir.getFileSystem(conf));
        Path absIndexesDir = indexesDir.makeQualified(indexesDir.getFileSystem(conf));
        if (this.fs.exists(indexDir)) {
            LOG.info("opening merged index in " + absIndexDir.toUri());
            this.searcher = new IndexSearcher(indexDir, this.conf);
        } else {
            if (!this.fs.exists(indexesDir)) {
                // should throw exception ?
                LOG.warn("Neither " + absIndexDir.toUri() + " nor " + absIndexesDir.toUri() + " found!");
            } else {
                LOG.info("opening indexes in " + absIndexesDir.toUri());
            }
            List<Path> vDirs = new ArrayList<Path>();
            FileStatus[] fstats = fs.listStatus(indexesDir, HadoopFSUtil.getPassDirectoriesFilter(fs));
            Path[] directories = HadoopFSUtil.getPaths(fstats);
            for (int i = 0; i < directories.length; i++) {
                Path indexdone = new Path(directories[i], Indexer.DONE_NAME);
                if (fs.isFile(indexdone)) {
                    vDirs.add(directories[i]);
                }
            }

            directories = new Path[vDirs.size()];
            for (int i = 0; vDirs.size() > 0; i++) {
                directories[i] = vDirs.remove(0);
            }

            this.searcher = new IndexSearcher(directories, this.conf);
        }
    }

    @Override
    @Deprecated
    public Hits search(Query query, int numHits, String dedupField, String sortField, boolean reverse)
            throws IOException {
        query.setParams(
                new QueryParams(numHits, QueryParams.DEFAULT_MAX_HITS_PER_DUP, dedupField, sortField, reverse));
        return searcher.search(query);
    }

    @Override
    public Hits search(Query query) throws IOException {
        return searcher.search(query);
    }

    public String getExplanation(Query query, Hit hit) throws IOException {
        return searcher.getExplanation(query, hit);
    }

    public HitDetails getDetails(Hit hit) throws IOException {
        return searcher.getDetails(hit);
    }

    public HitDetails[] getDetails(Hit[] hits) throws IOException {
        return searcher.getDetails(hits);
    }

    public boolean ping() throws IOException {
        return true;
    }

    public void close() throws IOException {
        if (searcher != null) {
            searcher.close();
        }
        if (fs != null) {
            fs.close();
        }
    }

    public long getProtocolVersion(String protocol, long clientVersion) throws IOException {
        return VERSION;
    }

}