001/*
002 * Licensed to the Apache Software Foundation (ASF) under one
003 * or more contributor license agreements.  See the NOTICE file
004 * distributed with this work for additional information
005 * regarding copyright ownership.  The ASF licenses this file
006 * to you under the Apache License, Version 2.0 (the
007 * "License"); you may not use this file except in compliance
008 * with the License.  You may obtain a copy of the License at
009 *
010 *     http://www.apache.org/licenses/LICENSE-2.0
011 *
012 * Unless required by applicable law or agreed to in writing, software
013 * distributed under the License is distributed on an "AS IS" BASIS,
014 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
015 * See the License for the specific language governing permissions and
016 * limitations under the License.
017 */
018package org.apache.hadoop.hbase.replication;
019
020import java.util.ArrayList;
021import java.util.Collections;
022import java.util.List;
023import org.apache.hadoop.hbase.Cell;
024import org.apache.hadoop.hbase.HBaseInterfaceAudience;
025import org.apache.hadoop.hbase.regionserver.wal.WALUtil;
026import org.apache.hadoop.hbase.wal.WAL.Entry;
027import org.apache.yetus.audience.InterfaceAudience;
028
029/**
030 * A {@link WALEntryFilter} which contains multiple filters and applies them in chain order
031 */
032@InterfaceAudience.LimitedPrivate(HBaseInterfaceAudience.REPLICATION)
033public class ChainWALEntryFilter implements WALEntryFilter {
034
035  private final WALEntryFilter[] filters;
036  private WALCellFilter[] cellFilters;
037
038  public ChainWALEntryFilter(WALEntryFilter... filters) {
039    this.filters = filters;
040    initCellFilters();
041  }
042
043  public ChainWALEntryFilter(List<WALEntryFilter> filters) {
044    ArrayList<WALEntryFilter> rawFilters = new ArrayList<>(filters.size());
045    // flatten the chains
046    for (WALEntryFilter filter : filters) {
047      if (filter instanceof ChainWALEntryFilter) {
048        Collections.addAll(rawFilters, ((ChainWALEntryFilter) filter).filters);
049      } else {
050        rawFilters.add(filter);
051      }
052    }
053    this.filters = rawFilters.toArray(new WALEntryFilter[rawFilters.size()]);
054    initCellFilters();
055  }
056
057  public void initCellFilters() {
058    ArrayList<WALCellFilter> cellFilters = new ArrayList<>(filters.length);
059    for (WALEntryFilter filter : filters) {
060      if (filter instanceof WALCellFilter) {
061        cellFilters.add((WALCellFilter) filter);
062      }
063    }
064    this.cellFilters = cellFilters.toArray(new WALCellFilter[cellFilters.size()]);
065  }
066
067  @Override
068  public Entry filter(Entry entry) {
069    entry = filterEntry(entry);
070    if (entry == null) {
071      return null;
072    }
073
074    filterCells(entry);
075    return entry;
076  }
077
078  protected Entry filterEntry(Entry entry) {
079    for (WALEntryFilter filter : filters) {
080      if (entry == null) {
081        return null;
082      }
083      entry = filter.filter(entry);
084    }
085    return entry;
086  }
087
088  protected void filterCells(Entry entry) {
089    if (entry == null || cellFilters.length == 0) {
090      return;
091    }
092    WALUtil.filterCells(entry.getEdit(), c -> filterCell(entry, c));
093  }
094
095  private Cell filterCell(Entry entry, Cell cell) {
096    for (WALCellFilter filter : cellFilters) {
097      cell = filter.filterCell(entry, cell);
098      if (cell == null) {
099        break;
100      }
101    }
102    return cell;
103  }
104}