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.JDOQLEvaluator;
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.AbstractJDOQLQuery;
037 import org.datanucleus.util.NucleusLogger;
038
039 /**
040 * JDOQL query implementation. Delegates to the query-language-agnostic {@link QueryEvaluator} via
041 * its thin wrapper sub-class {@link JDOQueryEvaluator}.
042 *
043 * @author Marco หงุ่ยตระกูล-Schulze - marco at nightlabs dot de
044 */
045 public class JDOQLQuery extends AbstractJDOQLQuery
046 {
047 private static final long serialVersionUID = 1L;
048
049 // BEGIN DataNucleus 3.0.0-m6 and 3.0.0-release
050 public JDOQLQuery(ExecutionContext ec, AbstractJDOQLQuery q) {
051 super(ec, q);
052 }
053
054 public JDOQLQuery(ExecutionContext ec, String query) {
055 super(ec, query);
056 }
057
058 public JDOQLQuery(ExecutionContext ec) {
059 super(ec);
060 }
061 // END DataNucleus 3.0.0-m6 and 3.0.0-release
062
063 // BEGIN DataNucleus 3.0.1 and newer
064 // public JDOQLQuery(StoreManager storeMgr, ExecutionContext ec, AbstractJDOQLQuery q) {
065 // super(storeMgr, ec, q);
066 // }
067 //
068 // public JDOQLQuery(StoreManager storeMgr, ExecutionContext ec, String query) {
069 // super(storeMgr, ec, query);
070 // }
071 //
072 // public JDOQLQuery(StoreManager storeMgr, ExecutionContext ec) {
073 // super(storeMgr, ec);
074 // }
075 // END DataNucleus 3.0.1 and newer
076
077 @Override
078 protected Object performExecute(@SuppressWarnings("rawtypes") Map parameters)
079 {
080 ManagedConnection mconn = ec.getStoreManager().getConnection(ec);
081 try {
082 PersistenceManagerConnection pmConn = (PersistenceManagerConnection)mconn.getConnection();
083 PersistenceManager pmData = pmConn.getDataPM();
084
085 boolean inMemory = evaluateInMemory();
086 boolean inMemory_applyFilter = true;
087 List<Object> candidates = null;
088 if (this.candidateCollection != null) {
089 if (candidateCollection.isEmpty())
090 {
091 return Collections.EMPTY_LIST;
092 }
093
094 @SuppressWarnings("unchecked")
095 Collection<? extends Object> c = this.candidateCollection;
096 candidates = new ArrayList<Object>(c);
097 }
098 else {
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 JDOQLEvaluator(this, candidates, compilation, parameters, ec.getClassLoaderResolver());
138 return evaluator.execute(inMemory_applyFilter, true, true, true, true);
139 } finally {
140 mconn.release();
141 }
142 }
143
144 }