/*
 * Copyright (C) 2005-2012 Alfresco Software Limited.
 *
 * This file is part of Alfresco
 *
 * Alfresco is free software: you can redistribute it and/or modify
 * it under the terms of the GNU Lesser General Public License as published by
 * the Free Software Foundation, either version 3 of the License, or
 * (at your option) any later version.
 *
 * Alfresco is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 * GNU Lesser General Public License for more details.
 *
 * You should have received a copy of the GNU Lesser General Public License
 * along with Alfresco. If not, see <http://www.gnu.org/licenses/>.
 */
package org.alfresco.repo.cache;

import java.io.Serializable;
import java.util.Map;

import org.hibernate.cache.Cache;
import org.hibernate.cache.CacheException;
import org.hibernate.cache.Timestamper;

/**
 * Adapts a {@link SimpleCache} instance for use as a Hibernate {@link Cache}.
 *
 * @author Matt Ward
 */
public class HibernateSimpleCacheAdapter implements Cache
{
    private final SimpleCache<Serializable, Object> cache;
    private final String regionName;
    
    /**
     * Adapt a 
     * @param cache
     * @param regionName
     */
    public HibernateSimpleCacheAdapter(SimpleCache<Serializable, Object> cache, String regionName)
    {
        this.cache = cache;
        this.regionName = regionName;
    }

    @Override
    public Object read(Object key) throws CacheException
    {
        return cache.get(serializable(key));
    }

    @Override
    public Object get(Object key) throws CacheException
    {
        return cache.get(serializable(key));
    }

    @Override
    public void put(Object key, Object value) throws CacheException
    {
        cache.put(serializable(key), value);
    }

    @Override
    public void update(Object key, Object value) throws CacheException
    {
        cache.put(serializable(key), value);
    }

    @Override
    public void remove(Object key) throws CacheException
    {
        cache.remove(serializable(key));
    }

    @Override
    public void clear() throws CacheException
    {
        cache.clear();
    }

    @Override
    public void destroy() throws CacheException
    {
        // NoOp
    }

    @Override
    public void lock(Object key) throws CacheException
    {
        // NoOp
    }

    @Override
    public void unlock(Object key) throws CacheException
    {
        // NoOp
    }

    @Override
    public long nextTimestamp()
    {
        return Timestamper.next();
    }

    @Override
    public int getTimeout()
    {
        return Timestamper.ONE_MS * 60000; // 1 minute
    }

    @Override
    public String getRegionName()
    {
        return regionName;
    }

    @Override
    public long getSizeInMemory()
    {
        return -1;
    }

    @Override
    public long getElementCountInMemory()
    {
        return -1;
    }

    @Override
    public long getElementCountOnDisk()
    {
        return 0;
    }

    @Override
    public Map toMap()
    {
        throw new UnsupportedOperationException();
    }

    private Serializable serializable(Object obj)
    {
        if (!(obj instanceof Serializable))
        {
            throw new IllegalArgumentException("Object is not Serializable, class=" + obj.getClass().getName());
        }
        return (Serializable) obj;
    }
    
}