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.FieldMeta;
030    import org.cumulus4j.store.model.IndexEntry;
031    import org.cumulus4j.store.model.IndexEntryFactory;
032    import org.cumulus4j.store.model.IndexValue;
033    import org.cumulus4j.store.query.QueryEvaluator;
034    import org.cumulus4j.store.query.eval.ExpressionHelper;
035    import org.cumulus4j.store.query.eval.InvokeExpressionEvaluator;
036    import org.cumulus4j.store.query.eval.PrimaryExpressionResolver;
037    import org.cumulus4j.store.query.eval.ResultDescriptor;
038    import org.datanucleus.query.expression.Expression;
039    import org.datanucleus.query.expression.PrimaryExpression;
040    import org.datanucleus.store.ExecutionContext;
041    
042    /**
043     * Evaluator for "Date.getSecond() {oper} {compareTo}".
044     */
045    public class DateGetSecondEvaluator extends AbstractMethodEvaluator {
046    
047            /* (non-Javadoc)
048             * @see org.cumulus4j.store.query.method.AbstractMethodEvaluator#requiresComparisonArgument()
049             */
050            @Override
051            public boolean requiresComparisonArgument() {
052                    return true;
053            }
054    
055            /* (non-Javadoc)
056             * @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)
057             */
058            @Override
059            public Set<Long> evaluate(QueryEvaluator queryEval,
060                            InvokeExpressionEvaluator invokeExprEval, Expression invokedExpr,
061                            ResultDescriptor resultDesc) {
062                    if (invokeExprEval.getExpression().getArguments().size() != 0)
063                            throw new IllegalStateException("Date.getSecond(...) expects no arguments, but there are " +
064                                            invokeExprEval.getExpression().getArguments().size());
065    
066                    if (invokedExpr instanceof PrimaryExpression) {
067                            return new MethodResolver(invokeExprEval, queryEval, (PrimaryExpression) invokedExpr,
068                                            compareToArgument, resultDesc.isNegated()).query();
069                    }
070                    else {
071                            if (!invokeExprEval.getLeft().getResultSymbols().contains(resultDesc.getSymbol()))
072                                    return null;
073    
074                            return queryEvaluate(invokeExprEval, queryEval, resultDesc.getFieldMeta(),
075                                            compareToArgument, resultDesc.isNegated());
076                    }
077            }
078    
079            private Set<Long> queryEvaluate(
080                            InvokeExpressionEvaluator invokeExprEval,
081                            QueryEvaluator queryEval,
082                            FieldMeta fieldMeta,
083                            Object compareToArgument, // the yyy in 'getSecond() >= yyy'
084                            boolean negate
085            ) {
086                    CryptoContext cryptoContext = queryEval.getCryptoContext();
087                    ExecutionContext executionContext = queryEval.getExecutionContext();
088                    IndexEntryFactory indexEntryFactory = queryEval.getStoreManager().getIndexFactoryRegistry().getIndexEntryFactory(
089                                    executionContext, fieldMeta, true
090                    );
091    
092                    Query q = queryEval.getPersistenceManagerForIndex().newQuery(indexEntryFactory.getIndexEntryClass());
093                    q.setFilter(
094                                    "this.fieldMeta == :fieldMeta && this.indexKey.getSecond() " +
095                                    ExpressionHelper.getOperatorAsJDOQLSymbol(invokeExprEval.getParent().getExpression().getOperator(), negate) +
096                                    " :compareToArgument"
097                    );
098                    Map<String, Object> params = new HashMap<String, Object>(2);
099                    params.put("fieldMeta", fieldMeta);
100                    params.put("compareToArgument", compareToArgument);
101    
102                    @SuppressWarnings("unchecked")
103                    Collection<? extends IndexEntry> indexEntries = (Collection<? extends IndexEntry>) q.executeWithMap(params);
104    
105                    Set<Long> result = new HashSet<Long>();
106                    for (IndexEntry indexEntry : indexEntries) {
107                            IndexValue indexValue = queryEval.getEncryptionHandler().decryptIndexEntry(cryptoContext, indexEntry);
108                            result.addAll(indexValue.getDataEntryIDs());
109                    }
110                    q.closeAll();
111                    return result;
112            }
113    
114            private class MethodResolver extends PrimaryExpressionResolver
115            {
116                    private InvokeExpressionEvaluator invokeExprEval;
117                    private Object compareToArgument;
118                    private boolean negate;
119    
120                    public MethodResolver(
121                                    InvokeExpressionEvaluator invokeExprEval,
122                                    QueryEvaluator queryEvaluator, PrimaryExpression primaryExpression,
123                                    Object compareToArgument,
124                                    boolean negate
125                    )
126                    {
127                            super(queryEvaluator, primaryExpression);
128                            this.invokeExprEval = invokeExprEval;
129                            this.compareToArgument = compareToArgument;
130                            this.negate = negate;
131                    }
132    
133                    @Override
134                    protected Set<Long> queryEnd(FieldMeta fieldMeta) {
135                            return queryEvaluate(invokeExprEval, queryEvaluator, fieldMeta, compareToArgument, negate);
136                    }
137            }
138    }