| /* |
| * 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.tephra.hbase96.coprocessor; |
| |
| import org.apache.hadoop.hbase.Cell; |
| import org.apache.hadoop.hbase.KeyValue; |
| import org.apache.hadoop.hbase.filter.Filter; |
| import org.apache.hadoop.hbase.filter.FilterBase; |
| |
| import java.io.IOException; |
| import java.util.List; |
| |
| /** |
| * {@link Filter} that encapsulates another {@link Filter}. It remembers the last {@link KeyValue} |
| * for which the underlying filter returned the {@link ReturnCode#NEXT_COL} or {@link ReturnCode#INCLUDE_AND_NEXT_COL}, |
| * so that when {@link #filterKeyValue} is called again for the same {@link KeyValue} with different |
| * version, it returns {@link ReturnCode#NEXT_COL} directly without consulting the underlying {@link Filter}. |
| * Please see TEPHRA-169 for more details. |
| */ |
| public class CellSkipFilter extends FilterBase { |
| private final Filter filter; |
| // remember the previous keyvalue processed by filter when the return code was NEXT_COL or INCLUDE_AND_NEXT_COL |
| private KeyValue skipColumn = null; |
| |
| public CellSkipFilter(Filter filter) { |
| this.filter = filter; |
| } |
| |
| /** |
| * Determines whether the current cell should be skipped. The cell will be skipped |
| * if the previous keyvalue had the same key as the current cell. This means filter already responded |
| * for the previous keyvalue with ReturnCode.NEXT_COL or ReturnCode.INCLUDE_AND_NEXT_COL. |
| * @param cell the {@link Cell} to be tested for skipping |
| * @return true is current cell should be skipped, false otherwise |
| */ |
| private boolean skipCellVersion(Cell cell) { |
| return skipColumn != null |
| && skipColumn.matchingRow(cell.getRowArray(), cell.getRowOffset(), cell.getRowLength()) |
| && skipColumn.matchingColumn(cell.getFamilyArray(), cell.getFamilyOffset(), cell.getFamilyLength(), |
| cell.getQualifierArray(), cell.getQualifierOffset(), cell.getQualifierLength()); |
| } |
| |
| @Override |
| public ReturnCode filterKeyValue(Cell cell) throws IOException { |
| if (skipCellVersion(cell)) { |
| return ReturnCode.NEXT_COL; |
| } |
| |
| ReturnCode code = filter.filterKeyValue(cell); |
| if (code == ReturnCode.NEXT_COL || code == ReturnCode.INCLUDE_AND_NEXT_COL) { |
| // only store the reference to the keyvalue if we are returning NEXT_COL or INCLUDE_AND_NEXT_COL |
| skipColumn = KeyValue.createFirstOnRow(cell.getRowArray(), cell.getRowOffset(), cell.getRowLength(), |
| cell.getFamilyArray(), cell.getFamilyOffset(), cell.getFamilyLength(), |
| cell.getQualifierArray(), cell.getQualifierOffset(), |
| cell.getQualifierLength()); |
| } else { |
| skipColumn = null; |
| } |
| return code; |
| } |
| |
| @Override |
| public boolean filterRow() throws IOException { |
| return filter.filterRow(); |
| } |
| |
| @Override |
| public Cell transformCell(Cell cell) throws IOException { |
| return filter.transformCell(cell); |
| } |
| |
| @Override |
| public void reset() throws IOException { |
| filter.reset(); |
| } |
| |
| @Override |
| public boolean filterRowKey(byte[] buffer, int offset, int length) throws IOException { |
| return filter.filterRowKey(buffer, offset, length); |
| } |
| |
| @Override |
| public boolean filterAllRemaining() throws IOException { |
| return filter.filterAllRemaining(); |
| } |
| |
| @Override |
| public void filterRowCells(List<Cell> kvs) throws IOException { |
| filter.filterRowCells(kvs); |
| } |
| |
| @Override |
| public boolean hasFilterRow() { |
| return filter.hasFilterRow(); |
| } |
| |
| @SuppressWarnings("deprecation") |
| @Override |
| public KeyValue getNextKeyHint(KeyValue currentKV) throws IOException { |
| return filter.getNextKeyHint(currentKV); |
| } |
| |
| @Override |
| public Cell getNextCellHint(Cell currentKV) throws IOException { |
| return filter.getNextCellHint(currentKV); |
| } |
| |
| @Override |
| public boolean isFamilyEssential(byte[] name) throws IOException { |
| return filter.isFamilyEssential(name); |
| } |
| |
| @Override |
| public byte[] toByteArray() throws IOException { |
| return filter.toByteArray(); |
| } |
| } |
| |