001/* 002 * (C) Copyright 2006-2011 Nuxeo SA (http://nuxeo.com/) and others. 003 * 004 * Licensed under the Apache License, Version 2.0 (the "License"); 005 * you may not use this file except in compliance with the License. 006 * You may obtain a copy of the License at 007 * 008 * http://www.apache.org/licenses/LICENSE-2.0 009 * 010 * Unless required by applicable law or agreed to in writing, software 011 * distributed under the License is distributed on an "AS IS" BASIS, 012 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. 013 * See the License for the specific language governing permissions and 014 * limitations under the License. 015 * 016 * Contributors: 017 * Florent Guillaume 018 */ 019package org.nuxeo.ecm.core.storage.sql.jdbc; 020 021import java.util.ArrayList; 022import java.util.Collections; 023import java.util.HashSet; 024import java.util.List; 025import java.util.Set; 026 027import org.apache.commons.logging.Log; 028import org.apache.commons.logging.LogFactory; 029import org.nuxeo.ecm.core.query.sql.NXQL; 030import org.nuxeo.runtime.model.ComponentInstance; 031import org.nuxeo.runtime.model.DefaultComponent; 032 033/** 034 * Service for the registration of QueryMaker classes. 035 */ 036public class QueryMakerServiceImpl extends DefaultComponent implements QueryMakerService { 037 038 private static final Log log = LogFactory.getLog(QueryMakerServiceImpl.class); 039 040 public static final String XP = "queryMaker"; 041 042 protected final List<QueryMakerDescriptor> descriptors = new ArrayList<>(2); 043 044 protected List<Class<? extends QueryMaker>> queryMakers; 045 046 @Override 047 public void registerContribution(Object contribution, String extensionPoint, ComponentInstance contributor) { 048 if (XP.equals(extensionPoint)) { 049 registerQueryMaker((QueryMakerDescriptor) contribution); 050 } 051 } 052 053 @Override 054 public void unregisterContribution(Object contribution, String extensionPoint, ComponentInstance contributor) { 055 if (XP.equals(extensionPoint)) { 056 unregisterQueryMaker((QueryMakerDescriptor) contribution); 057 } 058 } 059 060 @Override 061 public void registerQueryMaker(QueryMakerDescriptor descriptor) { 062 if (descriptor.enabled) { 063 log.info(String.format("Registering QueryMaker '%s': %s", descriptor.name, descriptor.queryMaker.getName())); 064 } else { 065 log.info(String.format("Disabling QueryMaker '%s'", descriptor.name)); 066 } 067 descriptors.add(descriptor); 068 queryMakers = null; 069 } 070 071 @Override 072 public void unregisterQueryMaker(QueryMakerDescriptor descriptor) { 073 if (descriptor.enabled) { 074 log.info(String.format("Unregistering QueryMaker '%s': %s", descriptor.name, 075 descriptor.queryMaker.getName())); 076 } else { 077 log.info(String.format("Unregistering disabled QueryMaker '%s'", descriptor.name)); 078 } 079 descriptors.remove(descriptor); 080 queryMakers = null; 081 } 082 083 @Override 084 public synchronized List<Class<? extends QueryMaker>> getQueryMakers() { 085 if (queryMakers == null) { 086 // recompute queryMakers 087 queryMakers = new ArrayList<>(2); 088 List<QueryMakerDescriptor> qmdl = new ArrayList<>(descriptors); 089 Collections.reverse(qmdl); 090 Set<String> done = new HashSet<>(); 091 for (QueryMakerDescriptor descriptor : qmdl) { 092 if (!done.add(descriptor.name)) { 093 continue; 094 } 095 if (descriptor.enabled) { 096 queryMakers.add(descriptor.queryMaker); 097 } 098 } 099 Collections.reverse(queryMakers); 100 // BBB backward compat 101 if (queryMakers.isEmpty() && !done.contains(NXQL.NXQL)) { 102 queryMakers.add(NXQLQueryMaker.class); 103 } 104 } 105 return queryMakers; 106 } 107}