| /* |
| * 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. |
| */ |
| package org.apache.phoenix.iterate; |
| |
| import java.util.List; |
| |
| import org.apache.hadoop.hbase.client.Scan; |
| import org.apache.phoenix.compile.QueryPlan; |
| import org.apache.phoenix.schema.PTable; |
| import org.apache.phoenix.schema.PTable.IndexType; |
| import org.apache.phoenix.schema.SaltingUtil; |
| import org.apache.phoenix.util.ScanUtil; |
| |
| /** |
| * Default implementation that creates a scan group if a plan is row key ordered (which requires a merge sort), |
| * or if a scan crosses a region boundary and the table is salted or a local index. |
| */ |
| public class DefaultParallelScanGrouper implements ParallelScanGrouper { |
| |
| private static final DefaultParallelScanGrouper INSTANCE = new DefaultParallelScanGrouper(); |
| |
| public static DefaultParallelScanGrouper getInstance() { |
| return INSTANCE; |
| } |
| |
| private DefaultParallelScanGrouper() {} |
| |
| @Override |
| public boolean shouldStartNewScan(QueryPlan plan, List<Scan> scans, byte[] startKey, boolean crossedRegionBoundary) { |
| PTable table = plan.getTableRef().getTable(); |
| boolean startNewScanGroup = false; |
| if (!plan.isRowKeyOrdered()) { |
| startNewScanGroup = true; |
| } else if (crossedRegionBoundary) { |
| if (table.getIndexType() == IndexType.LOCAL) { |
| startNewScanGroup = true; |
| } else if (table.getBucketNum() != null) { |
| startNewScanGroup = scans.isEmpty() || |
| ScanUtil.crossesPrefixBoundary(startKey, |
| ScanUtil.getPrefix(scans.get(scans.size()-1).getStartRow(), SaltingUtil.NUM_SALTING_BYTES), |
| SaltingUtil.NUM_SALTING_BYTES); |
| } |
| } |
| return startNewScanGroup; |
| } |
| |
| } |