Java tutorial
package de.metas.ui.web.window.model.lookup; import java.lang.ref.WeakReference; import java.util.ArrayList; import java.util.Comparator; import java.util.Iterator; import java.util.List; import java.util.Set; import java.util.concurrent.ConcurrentHashMap; import org.adempiere.ad.table.api.IADTableDAO; import org.compiere.model.I_AD_Column; import org.slf4j.Logger; import com.google.common.base.Predicates; import de.metas.cache.CCache; import de.metas.cache.CCache.CCacheStats; import de.metas.logging.LogManager; import de.metas.ui.web.window.descriptor.LookupDescriptor; import de.metas.ui.web.window.descriptor.LookupDescriptorProvider.LookupScope; import de.metas.ui.web.window.descriptor.sql.SqlLookupDescriptor; import de.metas.util.GuavaCollectors; import de.metas.util.Services; import lombok.NonNull; import lombok.ToString; /* * #%L * metasfresh-webui-api * %% * Copyright (C) 2016 metas GmbH * %% * This program is free software: you can redistribute it and/or modify * it under the terms of the GNU General Public License as * published by the Free Software Foundation, either version 2 of the * License, or (at your option) any later version. * * 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/gpl-2.0.html>. * #L% */ public final class LookupDataSourceFactory { public static final transient LookupDataSourceFactory instance = new LookupDataSourceFactory(); private static final Logger logger = LogManager.getLogger(LookupDataSourceFactory.class); private final CCache<LookupDescriptor, LookupDataSource> lookupDataSourcesCache = new CCache<>( "LookupDataSourcesCache", 300); private final ConcurrentHashMap<String, CacheInvalidationGroup> cacheInvalidationGroupsByTableName = new ConcurrentHashMap<>(); private LookupDataSourceFactory() { } public LookupDataSource searchInTableLookup(final String tableName) { final LookupDescriptor lookupDescriptor = SqlLookupDescriptor.searchInTable(tableName) .provideForScope(LookupScope.DocumentField); return getLookupDataSource(lookupDescriptor); } public LookupDataSource listByAD_Reference_Value_ID(final int AD_Reference_Value_ID) { final LookupDescriptor lookupDescriptor = SqlLookupDescriptor .listByAD_Reference_Value_ID(AD_Reference_Value_ID).provideForScope(LookupScope.DocumentField); return getLookupDataSource(lookupDescriptor); } public LookupDataSource searchByAD_Val_Rule_ID(final int AD_Reference_Value_ID, final int AD_Val_Rule_ID) { final LookupDescriptor lookupDescriptor = SqlLookupDescriptor .searchByAD_Val_Rule_ID(AD_Reference_Value_ID, AD_Val_Rule_ID) .provideForScope(LookupScope.DocumentField); return getLookupDataSource(lookupDescriptor); } public LookupDataSource searchByColumn(@NonNull final String tableName, @NonNull final String columnname) { final IADTableDAO adTableDAO = Services.get(IADTableDAO.class); final I_AD_Column column = adTableDAO.retrieveColumn(tableName, columnname); final LookupDescriptor lookupDescriptor = SqlLookupDescriptor .searchByAD_Val_Rule_ID(column.getAD_Reference_Value_ID(), column.getAD_Val_Rule_ID()) .provideForScope(LookupScope.DocumentField); return getLookupDataSource(lookupDescriptor); } public LookupDataSource getLookupDataSource(final LookupDescriptor lookupDescriptor) { return lookupDataSourcesCache.getOrLoad(lookupDescriptor, () -> createLookupDataSource(lookupDescriptor)); } public LookupDataSource createLookupDataSource(@NonNull final LookupDescriptor lookupDescriptor) { final LookupDataSourceFetcher fetcher = lookupDescriptor.getLookupDataSourceFetcher(); final LookupDataSource lookupDataSource; if (fetcher.isCached()) { lookupDataSource = LookupDataSourceAdapter.of(fetcher); } else if (!lookupDescriptor.isHighVolume() && !lookupDescriptor.hasParameters()) { lookupDataSource = FullyCachedLookupDataSource.of(fetcher); } else { final CachedLookupDataSourceFetcherAdapter cachedFetcher = CachedLookupDataSourceFetcherAdapter .of(fetcher); lookupDataSource = LookupDataSourceAdapter.of(cachedFetcher); } // // Register cache invalidation on depending table changed lookupDescriptor.getDependsOnTableNames().stream().map(this::getCacheInvalidationGroupByTableName) .forEach(cacheInvalidationGroup -> cacheInvalidationGroup.addLookupDataSource(lookupDataSource)); logger.debug("Creating lookup data source for {}: {}", lookupDescriptor, lookupDataSource); return lookupDataSource; } private CacheInvalidationGroup getCacheInvalidationGroupByTableName(final String tableName) { return cacheInvalidationGroupsByTableName.computeIfAbsent(tableName, CacheInvalidationGroup::new); } public void cacheInvalidateOnRecordsChanged(final Set<String> tableNames) { tableNames.stream().map(cacheInvalidationGroupsByTableName::get).filter(Predicates.notNull()) .forEach(CacheInvalidationGroup::cacheInvalidate); } public List<CCacheStats> getCacheStats() { return lookupDataSourcesCache.values().stream().flatMap(dataSource -> dataSource.getCacheStats().stream()) .distinct().sorted(Comparator.comparing(CCacheStats::getName)) .collect(GuavaCollectors.toImmutableList()); } @ToString(exclude = "lookupDataSources") private static final class CacheInvalidationGroup { private final String tableName; private final List<WeakReference<LookupDataSource>> lookupDataSources = new ArrayList<>(); public CacheInvalidationGroup(final String tableName) { this.tableName = tableName; } public void addLookupDataSource(@NonNull final LookupDataSource lookupDataSource) { synchronized (lookupDataSources) { lookupDataSources.add(new WeakReference<>(lookupDataSource)); } } private List<LookupDataSource> purgeAndGet() { synchronized (lookupDataSources) { final List<LookupDataSource> result = new ArrayList<>(lookupDataSources.size()); for (final Iterator<WeakReference<LookupDataSource>> it = lookupDataSources.iterator(); it .hasNext();) { final LookupDataSource lookupDataSource = it.next().get(); if (lookupDataSource == null) { it.remove(); continue; } result.add(lookupDataSource); } return result; } } public void cacheInvalidate() { for (final LookupDataSource lookupDataSource : purgeAndGet()) { try { lookupDataSource.cacheInvalidate(); logger.debug("Cache invalidated {} on {} record changed", lookupDataSource, tableName); } catch (final Exception ex) { logger.warn("Failed invalidating {}. Skipped", lookupDataSource, ex); } } } } }