001 /*
002 * Cumulus4j - Securing your data in the cloud - http://cumulus4j.org
003 * Copyright (C) 2011 NightLabs Consulting GmbH
004 *
005 * This program is free software: you can redistribute it and/or modify
006 * it under the terms of the GNU Affero General Public License as
007 * published by the Free Software Foundation, either version 3 of the
008 * License, or (at your option) any later version.
009 *
010 * This program is distributed in the hope that it will be useful,
011 * but WITHOUT ANY WARRANTY; without even the implied warranty of
012 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
013 * GNU Affero General Public License for more details.
014 *
015 * You should have received a copy of the GNU Affero General Public License
016 * along with this program. If not, see <http://www.gnu.org/licenses/>.
017 */
018 package org.cumulus4j.store.query;
019
020 import java.util.ArrayList;
021 import java.util.Collection;
022 import java.util.Collections;
023 import java.util.List;
024 import java.util.Map;
025 import java.util.Set;
026
027 import javax.jdo.PersistenceManager;
028
029 import org.cumulus4j.store.Cumulus4jStoreManager;
030 import org.cumulus4j.store.PersistenceManagerConnection;
031 import org.cumulus4j.store.model.ClassMeta;
032 import org.datanucleus.query.evaluator.JPQLEvaluator;
033 import org.datanucleus.query.evaluator.JavaQueryEvaluator;
034 import org.datanucleus.store.ExecutionContext;
035 import org.datanucleus.store.StoreManager;
036 import org.datanucleus.store.connection.ManagedConnection;
037 import org.datanucleus.store.query.AbstractJPQLQuery;
038 import org.datanucleus.util.NucleusLogger;
039
040 /**
041 * JPQL query implementation. Delegates to the query-language-agnostic {@link QueryEvaluator} via
042 * its thin wrapper sub-class {@link JDOQueryEvaluator}.
043 */
044 public class JPQLQuery extends AbstractJPQLQuery {
045
046 private static final long serialVersionUID = 1L;
047
048 // BEGIN DataNucleus 3.0.0-m6 and 3.0.0-release
049 // public JPQLQuery(ExecutionContext ec, AbstractJPQLQuery q) {
050 // super(ec, q);
051 // }
052 //
053 // public JPQLQuery(ExecutionContext ec, String query) {
054 // super(ec, query);
055 // }
056 //
057 // public JPQLQuery(ExecutionContext ec) {
058 // super(ec);
059 // }
060 // END DataNucleus 3.0.0-m6 and 3.0.0-release
061
062 // BEGIN DataNucleus 3.0.1 and newer
063 public JPQLQuery(StoreManager storeMgr, ExecutionContext ec, AbstractJPQLQuery q) {
064 super(storeMgr, ec, q);
065 }
066
067 public JPQLQuery(StoreManager storeMgr, ExecutionContext ec, String query) {
068 super(storeMgr, ec, query);
069 }
070
071 public JPQLQuery(StoreManager storeMgr, ExecutionContext ec) {
072 super(storeMgr, ec);
073 }
074 // END DataNucleus 3.0.1 and newer
075
076 @Override
077 protected Object performExecute(@SuppressWarnings("rawtypes") Map parameters) {
078 ManagedConnection mconn = ec.getStoreManager().getConnection(ec);
079 try {
080 PersistenceManagerConnection pmConn = (PersistenceManagerConnection)mconn.getConnection();
081 PersistenceManager pmData = pmConn.getDataPM();
082
083 boolean inMemory = evaluateInMemory();
084 boolean inMemory_applyFilter = true;
085 List<Object> candidates = null;
086 if (this.candidateCollection != null) {
087 if (candidateCollection.isEmpty()) {
088 return Collections.EMPTY_LIST;
089 }
090
091 @SuppressWarnings("unchecked")
092 Collection<? extends Object> c = this.candidateCollection;
093 candidates = new ArrayList<Object>(c);
094 }
095 else {
096 // http://sourceforge.net/tracker/?func=detail&aid=3514690&group_id=517465&atid=2102911
097 // Must NOT call this.setCandidateClass(...), because 1st it's already assigned and 2nd it clears the compilation.
098 // Marco :-)
099 // if (candidateExtent != null) {
100 // this.setCandidateClass(candidateExtent.getCandidateClass());
101 // this.setSubclasses(candidateExtent.hasSubclasses());
102 // }
103
104 if (inMemory) {
105 // Retrieve all candidates and perform all evaluation in-memory
106 Set<ClassMeta> classMetas = QueryHelper.getCandidateClassMetas((Cumulus4jStoreManager) ec.getStoreManager(),
107 ec, candidateClass, subclasses);
108 candidates = QueryHelper.getAllPersistentObjectsForCandidateClasses(pmData, ec, classMetas);
109 }
110 else {
111 try
112 {
113 // Apply filter in datastore
114 @SuppressWarnings("unchecked")
115 Map<String, Object> parameterValues = parameters;
116 JDOQueryEvaluator queryEvaluator = new JDOQueryEvaluator(this, compilation, parameterValues, clr, pmConn);
117 candidates = queryEvaluator.execute();
118 if (queryEvaluator.isComplete()) {
119 inMemory_applyFilter = false;
120 }
121 else {
122 NucleusLogger.QUERY.debug("Query evaluation of filter in datastore was incomplete so doing further work in-memory");
123 }
124 }
125 catch (UnsupportedOperationException uoe) {
126 // Some part of the filter is not yet supported, so fallback to in-memory evaluation
127 // Retrieve all candidates and perform all evaluation in-memory
128 NucleusLogger.QUERY.info("Query filter is not totally evaluatable in-datastore using Cumulus4j currently, so evaluating in-memory : "+uoe.getMessage());
129 Set<ClassMeta> classMetas = QueryHelper.getCandidateClassMetas((Cumulus4jStoreManager) ec.getStoreManager(),
130 ec, candidateClass, subclasses);
131 candidates = QueryHelper.getAllPersistentObjectsForCandidateClasses(pmData, ec, classMetas);
132 }
133 }
134 }
135
136 // Evaluate any remaining query components in-memory
137 JavaQueryEvaluator evaluator = new JPQLEvaluator(this, candidates, compilation, parameters, ec.getClassLoaderResolver());
138 return evaluator.execute(inMemory_applyFilter, true, true, true, true);
139 } finally {
140 mconn.release();
141 }
142 }
143 }