EHCacheImpl.java

/*
 * GovWay - A customizable API Gateway 
 * https://govway.org
 * 
 * Copyright (c) 2005-2025 Link.it srl (https://link.it). 
 * 
 * This program is free software: you can redistribute it and/or modify
 * it under the terms of the GNU General Public License version 3, as published by
 * the Free Software Foundation.
 *
 * This program 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 General Public License for more details.
 *
 * You should have received a copy of the GNU General Public License
 * along with this program.  If not, see <http://www.gnu.org/licenses/>.
 *
 */

package org.openspcoop2.utils.cache;

import java.io.OutputStream;
import java.io.Serializable;
import java.time.Duration;
import java.util.ArrayList;
import java.util.HashSet;
import java.util.List;
import java.util.Set;

import org.ehcache.Cache;
import org.ehcache.CacheManager;
import org.ehcache.config.CacheConfiguration;
import org.ehcache.config.builders.CacheConfigurationBuilder;
import org.ehcache.config.builders.CacheManagerBuilder;
import org.ehcache.config.builders.ExpiryPolicyBuilder;
import org.ehcache.config.builders.ResourcePoolsBuilder;
import org.ehcache.config.units.EntryUnit;
import org.ehcache.core.internal.statistics.DefaultStatisticsService;
import org.ehcache.core.spi.service.StatisticsService;
import org.ehcache.core.statistics.CacheStatistics;
import org.openspcoop2.utils.UtilsException;

/**
 * EHCacheImpl
 *
 * @author Poli Andrea (apoli@link.it)
 * @author $Author$
 * @version $Rev$, $Date$
 */
public class EHCacheImpl extends AbstractCacheImpl {

    private static CacheManager cacheManager;
    private static StatisticsService statisticsService;
    private static synchronized void initCacheManager() {
        if(cacheManager==null) {
            statisticsService = new DefaultStatisticsService();
            cacheManager = CacheManagerBuilder.newCacheManagerBuilder().using(statisticsService).build();
            cacheManager.init();
        }
    }

    private Cache<String, Serializable> cache = null;
    private int maxSize = -1;
    private int maxLifeTime = -1; // secondi
    

    public EHCacheImpl(String name) throws UtilsException{
        this(name, org.openspcoop2.utils.cache.Cache.DEFAULT_DISABLE_SYNCRONIZED_GET);
    }
    @Deprecated
    private EHCacheImpl(String name, boolean disableSyncronizedGet) throws UtilsException{
        super(CacheType.EH, name);
        if(cacheManager==null) {
            initCacheManager();
        }
    }
    
    
    //  *** Inizializzazione ***
    
    @Override
    public int getCacheSize() {
        return this.maxSize;
    }
    @Override
    public void setCacheSize(int cacheSize) {
        this.maxSize = cacheSize;
    }
    
    @Override
    public CacheAlgorithm getCacheAlgoritm() {
        return CacheAlgorithm.LRU;
    }
    @Override
    public void setCacheAlgoritm(CacheAlgorithm cacheAlgoritm) {
        // unsupported
    }
    
    @Override
    public long getItemIdleTime() throws UtilsException{
        return -1;
    }
    @Override
    public void setItemIdleTime(long itemIdleTimeCache) throws UtilsException{
        // unsupported
    }

    @Override
    public long getItemLifeTime() throws UtilsException{
        return this.maxLifeTime;
    }
    @Override
    public void setItemLifeTime(long itemLifeTimeCache) throws UtilsException{
        this.maxLifeTime = (int) itemLifeTimeCache;
    }
    
    @Override
    public void build() throws UtilsException{
        if ( this.maxSize <= 0 && this.maxLifeTime > 0 )
            throw new UtilsException( "Cannot use maxLifeTime without maxSize" );
        
        ResourcePoolsBuilder rpb = ResourcePoolsBuilder.newResourcePoolsBuilder();
        if(this.maxSize>0) {
            rpb = rpb.heap(this.maxSize, EntryUnit.ENTRIES);
        }
        
        CacheConfigurationBuilder<String,Serializable> ccb = CacheConfigurationBuilder.newCacheConfigurationBuilder(String.class, Serializable.class, rpb);
        if(this.maxLifeTime>0) {
            ccb = ccb.withExpiry(ExpiryPolicyBuilder.timeToLiveExpiration(Duration.ofSeconds(this.maxLifeTime)));
        }
        
        CacheConfiguration<String, Serializable> cacheConfiguration = ccb.build();
        this.cache = cacheManager.createCache(this.cacheName, cacheConfiguration);
    }
    
    
    
    
    
    //  *** Gestione ***
    
    @Override
    public void clear() throws UtilsException{
        this.cache.clear();
    }
    
    @Override
    public Object get(String key){
        return this.cache.get(key);
    }
    
    @Override
    public void remove(String key) throws UtilsException{
        try{
            this.cache.remove(key);
        }catch(Exception e){
            throw new UtilsException(e.getMessage(),e);
        }   
    }
    
    @Override
    public void put(String key,org.openspcoop2.utils.cache.CacheResponse value) throws UtilsException{
        try{
            this.cache.put(key, value);
        }catch(Exception e){
            throw new UtilsException(e.getMessage(),e);
        }
    }
    @Override
    public void put(String key,Serializable value) throws UtilsException{
        try{
            this.cache.put(key, value);
        }catch(Exception e){
            throw new UtilsException(e.getMessage(),e);
        }
    }
    
    @Override
    public int getItemCount()  throws UtilsException {
        CacheStatistics ehCacheStat = statisticsService.getCacheStatistics(this.cacheName);
        return (int) ehCacheStat.getTierStatistics().get("OnHeap").getMappings();//nb element in heap tier
    }
    
    @Override
    public List<String> keys() throws UtilsException {
        try{
            Set<String> set = new HashSet<>();
            this.cache.forEach(entry -> set.add(entry.getKey()));
            List<String> keys = new ArrayList<>();
            keys.addAll(set);
            return keys;
        }catch(Exception e){
            throw new UtilsException(e.getMessage(),e);
        }
    }
    
    
    

    
    
    //  *** Info ***
    
    @Override
    public void printStats(OutputStream out, String separator) throws UtilsException{
        
        try{
            
            StringBuilder bf = new StringBuilder();
            bf.append(this._printStats(separator, true));
            
            CacheStatistics ehCacheStat = statisticsService.getCacheStatistics(this.cacheName);
            
            bf.append("PutCount:");
            bf.append(ehCacheStat.getCachePuts());
            bf.append(" ");
            
            bf.append(separator);
            
            bf.append("HitCount(Aux):");
            bf.append(ehCacheStat.getCacheHits());
            bf.append(" ");
            
            bf.append(separator);
            
            bf.append("Evictions:");
            bf.append(ehCacheStat.getCacheEvictions());
            bf.append(" ");
            
            bf.append(separator);
            
            bf.append("MissCount(Expired):");
            bf.append(ehCacheStat.getCacheExpirations());
            bf.append(" ");
            
            bf.append(separator);
            
            bf.append("MissCount(NotFound):");
            bf.append(ehCacheStat.getCacheMisses());
            bf.append(" ");
            
            out.write(bf.toString().getBytes());
            
        }catch(Exception e){
            throw new UtilsException(e.getMessage(),e);
        }
    }
    
    /*
     * Non funziona!
    @Override
    protected long getByteCount() {
        CacheStatistics ehCacheStat = statisticsService.getCacheStatistics(this.cacheName);
        return ehCacheStat.getTierStatistics().get("OnHeap").getAllocatedByteSize();
    }
    */
}