com.hazelcast.hibernate.region.AbstractHazelcastRegion Maven / Gradle / Ivy

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/* 
 * Copyright (c) 2008-2010, Hazel Ltd. All Rights Reserved.
 * 
 * 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 com.hazelcast.hibernate.region;

import java.util.Map;

import org.hibernate.cache.CacheException;

import com.hazelcast.core.HazelcastInstance;
import com.hazelcast.core.IMap;
import com.hazelcast.core.MapEntry;
import com.hazelcast.hibernate.HazelcastTimestamper;

/**
 * @author Leo Kim ([email protected])
 */
abstract class AbstractHazelcastRegion implements HazelcastRegion {

	private final HazelcastInstance instance;
    private final IMap cache;
    private final String regionName;

    protected AbstractHazelcastRegion(final HazelcastInstance instance, final String regionName) {
    	super();
    	this.instance = instance;
        this.cache = instance.getMap(regionName);
        this.regionName = regionName;
    }

    public final IMap getCache() {
        return cache;
    }

    public void destroy() throws CacheException {
//    	Destroy of the region should not propagate 
//    	to other nodes of cluster.
//    	Do nothing on destroy.
    }

    /**
     * @return The size of the internal {@link IMap}.
     */
    public long getElementCountInMemory() {
        return getCache().size();
    }

    /**
     * Hazelcast does not support pushing elements to disk.
     *
     * @return -1 this value means "unsupported"
     */
    public long getElementCountOnDisk() {
        return -1;
    }

    /**
     * @return The name of the region.
     */
    public String getName() {
        return regionName;
    }

    /**
     * @return a rough estimate of number of bytes used by this region.
     */
    public long getSizeInMemory() {
        long size = 0;
        for (final Object key : getCache().keySet()) {
            final MapEntry entry = getCache().getMapEntry(key);
            if (entry != null) {
                size += entry.getCost();
            }
        }
        return size;
    }

    public int getTimeout() {
        return HazelcastTimestamper.getTimeout();
    }

    public long nextTimestamp() {
    	return HazelcastTimestamper.nextTimestamp(instance);
    }

    /**
     * Appears to be used only by org.hibernate.stat.SecondLevelCacheStatistics.
     *
     * @return the internal IMap used for this region.
     */
    public Map toMap() {
        return getCache();
    }
}