/* * (C) Copyright 2006-2011 Nuxeo SA (http://nuxeo.com/) and others. * * 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. * * Contributors: * Florent Guillaume */ package org.nuxeo.ecm.core.storage.sql.jdbc; import java.util.ArrayList; import java.util.Collections; import java.util.HashSet; import java.util.List; import java.util.Set; import org.apache.commons.logging.Log; import org.apache.commons.logging.LogFactory; import org.nuxeo.ecm.core.query.sql.NXQL; import org.nuxeo.runtime.model.ComponentInstance; import org.nuxeo.runtime.model.DefaultComponent; /** * Service for the registration of QueryMaker classes. */ public class QueryMakerServiceImpl extends DefaultComponent implements QueryMakerService { private static final Log log = LogFactory.getLog(QueryMakerServiceImpl.class); public static final String XP = "queryMaker"; protected final List<QueryMakerDescriptor> descriptors = new ArrayList<QueryMakerDescriptor>(2); protected List<Class<? extends QueryMaker>> queryMakers; @Override public void registerContribution(Object contribution, String extensionPoint, ComponentInstance contributor) { if (XP.equals(extensionPoint)) { registerQueryMaker((QueryMakerDescriptor) contribution); } } @Override public void unregisterContribution(Object contribution, String extensionPoint, ComponentInstance contributor) { if (XP.equals(extensionPoint)) { unregisterQueryMaker((QueryMakerDescriptor) contribution); } } @Override public void registerQueryMaker(QueryMakerDescriptor descriptor) { if (descriptor.enabled) { log.info(String.format("Registering QueryMaker '%s': %s", descriptor.name, descriptor.queryMaker.getName())); } else { log.info(String.format("Disabling QueryMaker '%s'", descriptor.name)); } descriptors.add(descriptor); queryMakers = null; } @Override public void unregisterQueryMaker(QueryMakerDescriptor descriptor) { if (descriptor.enabled) { log.info(String.format("Unregistering QueryMaker '%s': %s", descriptor.name, descriptor.queryMaker.getName())); } else { log.info(String.format("Unregistering disabled QueryMaker '%s'", descriptor.name)); } descriptors.remove(descriptor); queryMakers = null; } @Override public synchronized List<Class<? extends QueryMaker>> getQueryMakers() { if (queryMakers == null) { // recompute queryMakers queryMakers = new ArrayList<Class<? extends QueryMaker>>(2); List<QueryMakerDescriptor> qmdl = new ArrayList<QueryMakerDescriptor>(descriptors); Collections.reverse(qmdl); Set<String> done = new HashSet<String>(); for (QueryMakerDescriptor descriptor : qmdl) { if (!done.add(descriptor.name)) { continue; } if (descriptor.enabled) { queryMakers.add(descriptor.queryMaker); } } Collections.reverse(queryMakers); // BBB backward compat if (queryMakers.isEmpty() && !done.contains(NXQL.NXQL)) { queryMakers.add(NXQLQueryMaker.class); } } return queryMakers; } }