SingletonRedisRegionFactory.java

/*
 * Copyright (c) 2017. Sunghyouk Bae <sunghyouk.bae@gmail.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 org.hibernate.cache.redis.hibernate4;

import lombok.extern.slf4j.Slf4j;
import org.hibernate.cache.CacheException;
import org.hibernate.cache.redis.util.RedisCacheUtil;
import org.hibernate.cfg.Settings;

import java.util.Properties;
import java.util.concurrent.atomic.AtomicInteger;

/**
 * Singleton Hibernate 4.x 2nd Cache Region Factory using Redis
 *
 * @author sunghyouk.bae@gmail.com
 */
@Slf4j
public class SingletonRedisRegionFactory extends AbstractRedisRegionFactory {

  private static final AtomicInteger ReferenceCount = new AtomicInteger();

  public SingletonRedisRegionFactory(Properties props) {
    super(props);
    log.info("Create SingletonRedisRegionFactory instance.");
  }

  @Override
  public synchronized void start(Settings settings, Properties properties) throws CacheException {
    log.info("Starting SingletonRedisRegionFactory...");

    this.settings = settings;
    try {
      if (redis == null) {
        RedisCacheUtil.loadCacheProperties(properties);
        this.redis = createRedisClient();
        this.cacheTimestamper = createCacheTimestamper(redis, SingletonRedisRegionFactory.class.getName());
      }
      ReferenceCount.incrementAndGet();
      log.info("Started SingletonRedisRegionFactory");
    } catch (Exception e) {
      throw new CacheException(e);
    }
  }

  @Override
  public synchronized void stop() {
    log.debug("Stopping SingletonRedisRegionFactory...");

    if (ReferenceCount.decrementAndGet() == 0) {
      try {
        redis.shutdown();
        redis = null;
        cacheTimestamper = null;
        log.info("stopped SingletonRedisRegionFactory");
      } catch (Exception ignored) {
        log.warn("Error occurred in stopping hibernate-redis client.", ignored);
      }
    }
  }

  private static final long serialVersionUID = -7477946174209489184L;
}