IndexWriterCache.java

/*
 * Copyright (c) www.bugull.com
 * 
 * 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 net.tooan.ynpay.third.mongodb.cache;

import net.tooan.ynpay.third.jfinal.log.Logger;
import net.tooan.ynpay.third.mongodb.lucene.BuguIndex;
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 java.io.File;
import java.io.IOException;
import java.util.Map;
import java.util.concurrent.ConcurrentHashMap;
import java.util.concurrent.ConcurrentMap;

/**
 * Cache(Map) contains IndexWriter.
 *
 * @author Frank Wen(xbwen@hotmail.com)
 */
public class IndexWriterCache {

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

    private static IndexWriterCache instance = new IndexWriterCache();

    private final ConcurrentMap<String, IndexWriter> cache = new ConcurrentHashMap<String, IndexWriter>();

    private IndexWriterCache() {

    }

    public static IndexWriterCache getInstance() {
        return instance;
    }

    public IndexWriter get(String name) {
        IndexWriter writer = cache.get(name);
        if (writer != null) {
            return writer;
        }

        synchronized (this) {
            writer = cache.get(name);
            if (writer == null) {
                BuguIndex index = BuguIndex.getInstance();
                IndexWriterConfig conf = new IndexWriterConfig(index.getVersion(), index.getAnalyzer());
                double bufferSizeMB = index.getBufferSizeMB();
                conf.setRAMBufferSizeMB(bufferSizeMB);
                try {
                    String path = index.getDirectoryPath();
                    Directory directory = FSDirectory.open(new File(path + "/" + name));
                    writer = new IndexWriter(directory, conf);
                } catch (IOException ex) {
                    logger.error("Something is wrong when create IndexWriter for " + name, ex);
                }
                cache.put(name, writer);
            }
        }
        return writer;
    }

    public Map<String, IndexWriter> getAll() {
        return cache;
    }

}