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.method;
019
020 import java.util.Collection;
021 import java.util.HashMap;
022 import java.util.HashSet;
023 import java.util.Map;
024 import java.util.Set;
025
026 import javax.jdo.Query;
027
028 import org.cumulus4j.store.crypto.CryptoContext;
029 import org.cumulus4j.store.model.ClassMeta;
030 import org.cumulus4j.store.model.FieldMeta;
031 import org.cumulus4j.store.model.IndexEntry;
032 import org.cumulus4j.store.model.IndexEntryFactory;
033 import org.cumulus4j.store.model.IndexValue;
034 import org.cumulus4j.store.query.QueryEvaluator;
035 import org.cumulus4j.store.query.eval.ExpressionHelper;
036 import org.cumulus4j.store.query.eval.InvokeExpressionEvaluator;
037 import org.cumulus4j.store.query.eval.PrimaryExpressionResolver;
038 import org.cumulus4j.store.query.eval.ResultDescriptor;
039 import org.datanucleus.ExecutionContext;
040 import org.datanucleus.query.expression.Expression;
041 import org.datanucleus.query.expression.PrimaryExpression;
042
043 /**
044 * Evaluator for "String.substring(pos1 [, pos2]) {oper} {compareTo}".
045 */
046 public class StringSubstringEvaluator extends AbstractMethodEvaluator {
047
048 /* (non-Javadoc)
049 * @see org.cumulus4j.store.query.method.AbstractMethodEvaluator#requiresComparisonArgument()
050 */
051 @Override
052 public boolean requiresComparisonArgument() {
053 return true;
054 }
055
056 /* (non-Javadoc)
057 * @see org.cumulus4j.store.query.method.MethodEvaluator#evaluate(org.cumulus4j.store.query.QueryEvaluator, org.cumulus4j.store.query.eval.InvokeExpressionEvaluator, org.datanucleus.query.expression.Expression, org.cumulus4j.store.query.eval.ResultDescriptor)
058 */
059 @Override
060 public Set<Long> evaluate(QueryEvaluator queryEval,
061 InvokeExpressionEvaluator invokeExprEval, Expression invokedExpr,
062 ResultDescriptor resultDesc) {
063 if (invokeExprEval.getExpression().getArguments().size() < 1 || invokeExprEval.getExpression().getArguments().size() > 2)
064 throw new IllegalStateException("String.substring(...) expects 1 or 2 arguments, but there are " +
065 invokeExprEval.getExpression().getArguments().size());
066
067 // Evaluate the invoke argument
068 Object[] invokeArgs = ExpressionHelper.getEvaluatedInvokeArguments(queryEval, invokeExprEval.getExpression());
069
070 if (invokedExpr instanceof PrimaryExpression) {
071 return new MethodResolver(invokeExprEval, queryEval, (PrimaryExpression) invokedExpr, invokeArgs[0],
072 (invokeArgs.length > 1 ? invokeArgs[1] : null),
073 compareToArgument, resultDesc.isNegated()).query();
074 }
075 else {
076 if (!invokeExprEval.getLeft().getResultSymbols().contains(resultDesc.getSymbol()))
077 return null;
078
079 return queryEvaluate(invokeExprEval, queryEval, resultDesc.getFieldMeta(), invokeArgs[0],
080 (invokeArgs.length > 1 ? invokeArgs[1] : null), compareToArgument, resultDesc.isNegated());
081 }
082 }
083
084 private Set<Long> queryEvaluate(
085 InvokeExpressionEvaluator invokeExprEval,
086 QueryEvaluator queryEval,
087 FieldMeta fieldMeta,
088 Object invokeArg1, // the xxx1 in 'substring(xxx1)'
089 Object invokeArg2, // the xxx2 in 'substring(xxx1, xxx2)'
090 Object compareToArgument, // the yyy in 'substring(...) >= yyy'
091 boolean negate
092 ) {
093 CryptoContext cryptoContext = queryEval.getCryptoContext();
094 ExecutionContext executionContext = queryEval.getExecutionContext();
095 IndexEntryFactory indexEntryFactory = queryEval.getStoreManager().getIndexFactoryRegistry().getIndexEntryFactory(
096 executionContext, fieldMeta, true
097 );
098
099 Query q = queryEval.getPersistenceManagerForIndex().newQuery(indexEntryFactory.getIndexEntryClass());
100 q.setFilter(
101 "this.keyStoreRefID == :keyStoreRefID && this.fieldMeta_fieldID == :fieldMeta_fieldID && " +
102 (invokeArg2 != null ?
103 "this.indexKey.substring(" + invokeArg1 + "," + invokeArg2 +") " :
104 "this.indexKey.substring(" + invokeArg1 + ") ") +
105 ExpressionHelper.getOperatorAsJDOQLSymbol(invokeExprEval.getParent().getExpression().getOperator(), negate) +
106 " :compareToArgument"
107 );
108 Map<String, Object> params = new HashMap<String, Object>(2);
109 params.put("keyStoreRefID", cryptoContext.getKeyStoreRefID());
110 params.put("fieldMeta_fieldID", fieldMeta.getFieldID());
111 params.put("compareToArgument", compareToArgument);
112
113 @SuppressWarnings("unchecked")
114 Collection<? extends IndexEntry> indexEntries = (Collection<? extends IndexEntry>) q.executeWithMap(params);
115
116 Set<Long> result = new HashSet<Long>();
117 for (IndexEntry indexEntry : indexEntries) {
118 IndexValue indexValue = queryEval.getEncryptionHandler().decryptIndexEntry(cryptoContext, indexEntry);
119 result.addAll(indexValue.getDataEntryIDs());
120 }
121 q.closeAll();
122 return result;
123 }
124
125 private class MethodResolver extends PrimaryExpressionResolver
126 {
127 private InvokeExpressionEvaluator invokeExprEval;
128 private Object invokePos1;
129 private Object invokePos2;
130 private Object compareToArgument;
131 private boolean negate;
132
133 public MethodResolver(
134 InvokeExpressionEvaluator invokeExprEval,
135 QueryEvaluator queryEvaluator, PrimaryExpression primaryExpression,
136 Object invokeArg1, // the xxx in 'substring(xxx) >= yyy'
137 Object invokeArg2, // the xxx in 'substring(xxx1, xxx2) >= yyy'
138 Object compareToArgument, // the yyy in 'substring(xxx) >= yyy'
139 boolean negate
140 )
141 {
142 super(queryEvaluator, primaryExpression);
143 this.invokeExprEval = invokeExprEval;
144 this.invokePos1 = invokeArg1;
145 this.invokePos2 = invokeArg2;
146 this.compareToArgument = compareToArgument;
147 this.negate = negate;
148 }
149
150 @Override
151 protected Set<Long> queryEnd(FieldMeta fieldMeta, ClassMeta classMeta) {
152 return queryEvaluate(invokeExprEval, queryEvaluator, fieldMeta, invokePos1, invokePos2, compareToArgument, negate);
153 }
154 }
155 }