| package org.apache.rya.indexing.IndexPlanValidator; |
| |
| /* |
| * Licensed to the Apache Software Foundation (ASF) under one |
| * or more contributor license agreements. See the NOTICE file |
| * distributed with this work for additional information |
| * regarding copyright ownership. The ASF licenses this file |
| * to you under the Apache License, Version 2.0 (the |
| * "License"); you may not use this file except in compliance |
| * with the License. You may obtain a copy of the License at |
| * |
| * http://www.apache.org/licenses/LICENSE-2.0 |
| * |
| * Unless required by applicable law or agreed to in writing, |
| * software distributed under the License is distributed on an |
| * "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY |
| * KIND, either express or implied. See the License for the |
| * specific language governing permissions and limitations |
| * under the License. |
| */ |
| |
| import java.util.Iterator; |
| import java.util.List; |
| import java.util.NoSuchElementException; |
| |
| import org.apache.rya.indexing.external.tupleSet.ExternalTupleSet; |
| import org.apache.rya.indexing.pcj.matching.QueryVariableNormalizer; |
| import org.eclipse.rdf4j.query.algebra.Projection; |
| import org.eclipse.rdf4j.query.algebra.TupleExpr; |
| |
| import com.google.common.collect.Lists; |
| |
| public class IndexedExecutionPlanGenerator implements ExternalIndexMatcher { |
| |
| private final TupleExpr query; |
| private final List<ExternalTupleSet> normalizedIndexList; |
| |
| public IndexedExecutionPlanGenerator(TupleExpr query, List<ExternalTupleSet> indexList) { |
| this.query = query; |
| final VarConstantIndexListPruner vci = new VarConstantIndexListPruner(query); |
| normalizedIndexList = getNormalizedIndices(vci.getRelevantIndices(indexList)); |
| } |
| |
| public List<ExternalTupleSet> getNormalizedIndices() { |
| return normalizedIndexList; |
| } |
| |
| @Override |
| public Iterator<TupleExpr> getIndexedTuples() { |
| |
| final ValidIndexCombinationGenerator vic = new ValidIndexCombinationGenerator(query); |
| final Iterator<List<ExternalTupleSet>> iter = vic.getValidIndexCombos(normalizedIndexList); |
| return new Iterator<TupleExpr>() { |
| private TupleExpr next = null; |
| private boolean hasNextCalled = false; |
| private boolean isEmpty = false; |
| |
| @Override |
| public boolean hasNext() { |
| |
| if (!hasNextCalled && !isEmpty) { |
| while (iter.hasNext()) { |
| final TupleExpr temp = GeneralizedExternalProcessor.process(query, iter.next()); |
| if (temp != null) { |
| next = temp; |
| hasNextCalled = true; |
| return true; |
| } |
| } |
| isEmpty = true; |
| return false; |
| } else { |
| return !isEmpty; |
| } |
| } |
| |
| @Override |
| public TupleExpr next() { |
| |
| if (hasNextCalled) { |
| hasNextCalled = false; |
| return next; |
| } else if(isEmpty) { |
| throw new NoSuchElementException(); |
| }else { |
| if (this.hasNext()) { |
| hasNextCalled = false; |
| return next; |
| } else { |
| throw new NoSuchElementException(); |
| } |
| } |
| } |
| |
| @Override |
| public void remove() { |
| throw new UnsupportedOperationException("Cannot delete from iterator!"); |
| } |
| }; |
| } |
| |
| private List<ExternalTupleSet> getNormalizedIndices(List<ExternalTupleSet> indexSet) { |
| |
| ExternalTupleSet tempIndex; |
| final List<ExternalTupleSet> normalizedIndexSet = Lists.newArrayList(); |
| for (final ExternalTupleSet e : indexSet) { |
| List<TupleExpr> tupList = null; |
| try { |
| tupList = QueryVariableNormalizer.getNormalizedIndex(query, e.getTupleExpr()); |
| } catch (final Exception e1) { |
| e1.printStackTrace(); |
| throw new Error(e1); |
| } |
| |
| for (final TupleExpr te : tupList) { |
| tempIndex = (ExternalTupleSet) e.clone(); |
| tempIndex.setProjectionExpr((Projection) te); |
| normalizedIndexSet.add(tempIndex); |
| } |
| } |
| return normalizedIndexSet; |
| } |
| } |