| /** |
| * 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.hadoop.hbase.regionserver.querymatcher; |
| |
| import java.util.SortedSet; |
| import java.util.TreeSet; |
| |
| import org.apache.hadoop.hbase.classification.InterfaceAudience; |
| import org.apache.hadoop.hbase.Cell; |
| import org.apache.hadoop.hbase.CellComparator; |
| import org.apache.hadoop.hbase.CellUtil; |
| import org.apache.hadoop.hbase.KeyValue; |
| import org.apache.hadoop.hbase.util.Bytes; |
| |
| /** |
| * This class is responsible for the tracking and enforcement of Deletes during the course of a Scan |
| * operation. It only has to enforce Delete and DeleteColumn, since the DeleteFamily is handled at a |
| * higher level. |
| * <p> |
| * This class is utilized through three methods: |
| * <ul> |
| * <li>{@link #add} when encountering a Delete or DeleteColumn</li> |
| * <li>{@link #isDeleted} when checking if a Put KeyValue has been deleted</li> |
| * <li>{@link #update} when reaching the end of a StoreFile or row for scans</li> |
| * </ul> |
| * <p> |
| * This class is NOT thread-safe as queries are never multi-threaded |
| */ |
| @InterfaceAudience.Private |
| public class ScanDeleteTracker implements DeleteTracker { |
| |
| protected boolean hasFamilyStamp = false; |
| protected long familyStamp = 0L; |
| protected SortedSet<Long> familyVersionStamps = new TreeSet<Long>(); |
| protected byte[] deleteBuffer = null; |
| protected int deleteOffset = 0; |
| protected int deleteLength = 0; |
| protected byte deleteType = 0; |
| protected long deleteTimestamp = 0L; |
| |
| /** |
| * Add the specified KeyValue to the list of deletes to check against for this row operation. |
| * <p> |
| * This is called when a Delete is encountered. |
| * @param cell - the delete cell |
| */ |
| @Override |
| public void add(Cell cell) { |
| long timestamp = cell.getTimestamp(); |
| byte type = cell.getTypeByte(); |
| if (!hasFamilyStamp || timestamp > familyStamp) { |
| if (type == KeyValue.Type.DeleteFamily.getCode()) { |
| hasFamilyStamp = true; |
| familyStamp = timestamp; |
| return; |
| } else if (type == KeyValue.Type.DeleteFamilyVersion.getCode()) { |
| familyVersionStamps.add(timestamp); |
| return; |
| } |
| |
| if (deleteBuffer != null && type < deleteType) { |
| // same column, so ignore less specific delete |
| if (CellUtil.matchingQualifier(cell, deleteBuffer, deleteOffset, deleteLength)) { |
| return; |
| } |
| } |
| // new column, or more general delete type |
| deleteBuffer = cell.getQualifierArray(); |
| deleteOffset = cell.getQualifierOffset(); |
| deleteLength = cell.getQualifierLength(); |
| deleteType = type; |
| deleteTimestamp = timestamp; |
| } |
| // missing else is never called. |
| } |
| |
| /** |
| * Check if the specified KeyValue buffer has been deleted by a previously seen delete. |
| * @param cell - current cell to check if deleted by a previously seen delete |
| * @return deleteResult |
| */ |
| @Override |
| public DeleteResult isDeleted(Cell cell) { |
| long timestamp = cell.getTimestamp(); |
| if (hasFamilyStamp && timestamp <= familyStamp) { |
| return DeleteResult.FAMILY_DELETED; |
| } |
| |
| if (familyVersionStamps.contains(Long.valueOf(timestamp))) { |
| return DeleteResult.FAMILY_VERSION_DELETED; |
| } |
| |
| if (deleteBuffer != null) { |
| int ret = -(CellComparator.compareQualifiers(cell, deleteBuffer, deleteOffset, deleteLength)); |
| if (ret == 0) { |
| if (deleteType == KeyValue.Type.DeleteColumn.getCode()) { |
| return DeleteResult.COLUMN_DELETED; |
| } |
| // Delete (aka DeleteVersion) |
| // If the timestamp is the same, keep this one |
| if (timestamp == deleteTimestamp) { |
| return DeleteResult.VERSION_DELETED; |
| } |
| // use assert or not? |
| assert timestamp < deleteTimestamp; |
| |
| // different timestamp, let's clear the buffer. |
| deleteBuffer = null; |
| } else if (ret < 0) { |
| // Next column case. |
| deleteBuffer = null; |
| } else { |
| throw new IllegalStateException("isDelete failed: deleteBuffer=" |
| + Bytes.toStringBinary(deleteBuffer, deleteOffset, deleteLength) + ", qualifier=" |
| + Bytes.toStringBinary(cell.getQualifierArray(), cell.getQualifierOffset(), |
| cell.getQualifierLength()) |
| + ", timestamp=" + timestamp + ", comparison result: " + ret); |
| } |
| } |
| |
| return DeleteResult.NOT_DELETED; |
| } |
| |
| @Override |
| public boolean isEmpty() { |
| return deleteBuffer == null && !hasFamilyStamp && familyVersionStamps.isEmpty(); |
| } |
| |
| @Override |
| // called between every row. |
| public void reset() { |
| hasFamilyStamp = false; |
| familyStamp = 0L; |
| familyVersionStamps.clear(); |
| deleteBuffer = null; |
| } |
| |
| @Override |
| // should not be called at all even (!) |
| public void update() { |
| this.reset(); |
| } |
| } |