BerkeleyDbSearcher.java

package lia.tools;

/**
 * Copyright Manning Publications Co.
 *
 * 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 lan      
*/

import com.sleepycat.db.Environment;
import com.sleepycat.db.EnvironmentConfig;
import com.sleepycat.db.Database;
import com.sleepycat.db.DatabaseType;
import com.sleepycat.db.DatabaseConfig;
import com.sleepycat.db.DatabaseException;

import org.apache.lucene.index.Term;
import org.apache.lucene.search.TopDocs;
import org.apache.lucene.search.IndexSearcher;
import org.apache.lucene.search.TermQuery;
import org.apache.lucene.store.db.DbDirectory;

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

// From chapter 9
public class BerkeleyDbSearcher {
  public static void main(String[] args) throws IOException, DatabaseException {
    if (args.length != 1) {
      System.err.println("Usage: BerkeleyDbSearcher <index dir>");
      System.exit(-1);
    }
    File indexFile = new File(args[0]);

    EnvironmentConfig envConfig = new EnvironmentConfig();
    DatabaseConfig dbConfig = new DatabaseConfig();

    envConfig.setTransactional(true);
    envConfig.setInitializeCache(true);
    envConfig.setInitializeLocking(true);
    envConfig.setInitializeLogging(true);
    envConfig.setAllowCreate(true);
    envConfig.setThreaded(true);
    dbConfig.setAllowCreate(true);
    dbConfig.setType(DatabaseType.BTREE);

    Environment env = new Environment(indexFile, envConfig);

    Database index = env.openDatabase(null, "__index__", null, dbConfig);
    Database blocks = env.openDatabase(null, "__blocks__", null, dbConfig);

    DbDirectory directory = new DbDirectory(null, index, blocks, 0);

    IndexSearcher searcher = new IndexSearcher(directory, true);
    TopDocs hits = searcher.search(new TermQuery(new Term("contents", "fox")), 10);
    System.out.println(hits.totalHits + " documents found");
    searcher.close();

    index.close();
    blocks.close();
    env.close();
  }
}