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.connection.ManagedConnection;
036 import org.datanucleus.store.query.AbstractJPQLQuery;
037 import org.datanucleus.util.NucleusLogger;
038
039 /**
040 * JPQL query implementation. Delegates to the query-language-agnostic {@link QueryEvaluator} via
041 * its thin wrapper sub-class {@link JDOQueryEvaluator}.
042 */
043 public class JPQLQuery extends AbstractJPQLQuery {
044
045 private static final long serialVersionUID = 1L;
046
047 // BEGIN DataNucleus 3.0.0-m6 and 3.0.0-release
048 public JPQLQuery(ExecutionContext ec, AbstractJPQLQuery q) {
049 super(ec, q);
050 }
051
052 public JPQLQuery(ExecutionContext ec, String query) {
053 super(ec, query);
054 }
055
056 public JPQLQuery(ExecutionContext ec) {
057 super(ec);
058 }
059 // END DataNucleus 3.0.0-m6 and 3.0.0-release
060
061 // BEGIN DataNucleus 3.0.1 and newer
062 // public JPQLQuery(StoreManager storeMgr, ExecutionContext ec, AbstractJPQLQuery q) {
063 // super(storeMgr, ec, q);
064 // }
065 //
066 // public JPQLQuery(StoreManager storeMgr, ExecutionContext ec, String query) {
067 // super(storeMgr, ec, query);
068 // }
069 //
070 // public JPQLQuery(StoreManager storeMgr, ExecutionContext ec) {
071 // super(storeMgr, ec);
072 // }
073 // END DataNucleus 3.0.1 and newer
074
075 @Override
076 protected Object performExecute(@SuppressWarnings("rawtypes") Map parameters) {
077 ManagedConnection mconn = ec.getStoreManager().getConnection(ec);
078 try {
079 PersistenceManagerConnection pmConn = (PersistenceManagerConnection)mconn.getConnection();
080 PersistenceManager pmData = pmConn.getDataPM();
081
082 boolean inMemory = evaluateInMemory();
083 boolean inMemory_applyFilter = true;
084 List<Object> candidates = null;
085 if (this.candidateCollection != null) {
086 if (candidateCollection.isEmpty()) {
087 return Collections.EMPTY_LIST;
088 }
089
090 @SuppressWarnings("unchecked")
091 Collection<? extends Object> c = this.candidateCollection;
092 candidates = new ArrayList<Object>(c);
093 }
094 else {
095 if (candidateExtent != null) {
096 this.setCandidateClass(candidateExtent.getCandidateClass());
097 this.setSubclasses(candidateExtent.hasSubclasses());
098 }
099
100 if (inMemory) {
101 // Retrieve all candidates and perform all evaluation in-memory
102 Set<ClassMeta> classMetas = QueryHelper.getCandidateClassMetas((Cumulus4jStoreManager) ec.getStoreManager(),
103 ec, candidateClass, subclasses);
104 candidates = QueryHelper.getAllPersistentObjectsForCandidateClasses(pmData, ec, classMetas);
105 }
106 else {
107 try
108 {
109 // Apply filter in datastore
110 @SuppressWarnings("unchecked")
111 Map<String, Object> parameterValues = parameters;
112 JDOQueryEvaluator queryEvaluator = new JDOQueryEvaluator(this, compilation, parameterValues, clr, pmConn);
113 candidates = queryEvaluator.execute();
114 if (queryEvaluator.isComplete()) {
115 inMemory_applyFilter = false;
116 }
117 else {
118 NucleusLogger.QUERY.debug("Query evaluation of filter in datastore was incomplete so doing further work in-memory");
119 }
120 }
121 catch (UnsupportedOperationException uoe) {
122 // Some part of the filter is not yet supported, so fallback to in-memory evaluation
123 // Retrieve all candidates and perform all evaluation in-memory
124 NucleusLogger.QUERY.info("Query filter is not totally evaluatable in-datastore using Cumulus4j currently, so evaluating in-memory : "+uoe.getMessage());
125 Set<ClassMeta> classMetas = QueryHelper.getCandidateClassMetas((Cumulus4jStoreManager) ec.getStoreManager(),
126 ec, candidateClass, subclasses);
127 candidates = QueryHelper.getAllPersistentObjectsForCandidateClasses(pmData, ec, classMetas);
128 }
129 }
130 }
131
132 // Evaluate any remaining query components in-memory
133 JavaQueryEvaluator evaluator = new JPQLEvaluator(this, candidates, compilation, parameters, ec.getClassLoaderResolver());
134 return evaluator.execute(inMemory_applyFilter, true, true, true, true);
135 } finally {
136 mconn.release();
137 }
138 }
139 }