sascha@541: package de.intevation.gnv.geobackend.base.query;
sascha@541: 
sascha@541: import java.util.Collection;
tim@895: import java.util.Iterator;
sascha@541: 
sascha@541: import net.sf.ehcache.Cache;
sascha@886: import net.sf.ehcache.CacheManager;
sascha@541: import net.sf.ehcache.Element;
sascha@541: 
sascha@542: import org.apache.log4j.Logger;
sascha@541: 
tim@895: import de.intevation.gnv.geobackend.base.Result;
tim@895: import de.intevation.gnv.geobackend.base.query.cache.CacheCleaner;
ingo@1122: import de.intevation.gnv.geobackend.config.Configuration;
tim@895: 
sascha@541: /**
sascha@887:  * @author <a href="mailto:sascha.teichmann@intevation.de">Sascha L. Teichmann</a>
sascha@541:  */
sascha@541: public class CachingQueryExecutorFactory
sascha@541: extends      QueryExecutorFactory
sascha@541: {
sascha@541:     public static final String CACHE_NAME             = "sql.cache";
sascha@541: 
sascha@542:     private static Logger log = Logger.getLogger(CachingQueryExecutorFactory.class);
sascha@542: 
sascha@541:     protected CacheManager manager;
sascha@541: 
sascha@541:     public CachingQueryExecutorFactory() {
sascha@542:         log.info("using SQL cache");
ingo@1122: 
ingo@1122:         init();
ingo@1122:     }
ingo@1122: 
ingo@1122:     private void init() {
ingo@1122:         Configuration config = Configuration.getInstance();
ingo@1122: 
ingo@1122:         if (config == null) {
ingo@1122:             log.error("No geobackend configuration found. " +
ingo@1122:                 "Wasn't able to initialize cache.");
ingo@1122:             return;
ingo@1122:         }
ingo@1122:         else {
ingo@1122:             String configFile = config.getCacheConfiguration();
ingo@1122:             manager = configFile != null
ingo@1122:                 ? new CacheManager(configFile)
ingo@1122:                 : new CacheManager();
ingo@1122:             manager.addCache(CACHE_NAME);
ingo@1122:             CacheCleaner cc = new CacheCleaner();
ingo@1122:             cc.start();
ingo@1122:         }
sascha@541:     }
sascha@541: 
sascha@541:     public QueryExecutor getQueryExecutor() {
sascha@541:         return new DefaultQueryExceutor() {
sascha@541: 
sascha@541:             public Collection<Result> cachedResults(String query) {
sascha@541:                 Cache   cache   = manager.getCache(CACHE_NAME);
sascha@541:                 Element element = cache.get(query);
sascha@542:                 if (log.isDebugEnabled()) {
sascha@542:                     log.debug("found results in SQL cache: " + (element != null));
sascha@542:                 }
sascha@541:                 return element != null
sascha@541:                     ? (Collection<Result>)element.getObjectValue()
sascha@541:                     : null;
sascha@541:             }
sascha@541: 
sascha@542:             public void cacheResults(String query, Collection<Result> results) {
sascha@542:                 log.debug("store results in SQL cache");
sascha@541:                 Cache cache = manager.getCache(CACHE_NAME);
sascha@541:                 cache.put(new Element(query, results));
sascha@541:             }
ingo@897: 
tim@895:             public void clearCache(String[] tableNames) {
tim@895:                 Cache   cache   = manager.getCache(CACHE_NAME);
tim@895:                 Iterator keys = cache.getKeys().iterator();
tim@895:                 while (keys.hasNext()){
tim@895:                     String origKey = (String)keys.next();
tim@895:                     String key = origKey.toUpperCase();
tim@895:                     log.debug(key);
tim@895:                     for (int i = 0; i < tableNames.length; i++){
tim@895:                         if (key.contains(tableNames[i])){
tim@895:                             log.debug(tableNames[i]+ " is contained in "+key);
tim@895:                             log.debug("Cacheentry will be removed");
tim@895:                             boolean success = cache.remove(origKey);
tim@895:                             if (!success){
tim@895:                                 log.warn("Object could not be reoved from Cache.");
tim@895:                             }
tim@895:                             break;
tim@895:                         }
tim@895:                     }
tim@895:                 }
tim@895:             }
sascha@541:         };
sascha@541:     }
sascha@542: 
sascha@542:     public void shutdown() {
sascha@542:         log.info("shutting down SQL cache");
sascha@542:         manager.getCache(CACHE_NAME).flush();
sascha@542:         manager.shutdown();
sascha@542:     }
sascha@541: }
sascha@541: // vim:set ts=4 sw=4 si et sta sts=4 fenc=utf8: