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.filter;
019
020import java.io.IOException;
021import java.util.ArrayList;
022import java.util.List;
023import org.apache.hadoop.hbase.Cell;
024import org.apache.hadoop.hbase.CellComparator;
025import org.apache.yetus.audience.InterfaceAudience;
026
027/**
028 * Base class for FilterList. Currently, we have two sub-classes to extend this class:
029 * {@link FilterListWithOR}, {@link FilterListWithAND}.
030 */
031@InterfaceAudience.Private
032public abstract class FilterListBase extends FilterBase {
033  private static final int MAX_LOG_FILTERS = 5;
034  protected final ArrayList<Filter> filters;
035  /**
036   * For each sub-filter in filter list, we save a boolean flag to indicate that whether the return
037   * code of filterCell(c) for sub-filter is INCLUDE* (INCLUDE, INCLUDE_AND_NEXT_COL,
038   * INCLUDE_AND_SEEK_NEXT_ROW) case. if true, we need to transform cell for the sub-filter.
039   */
040  protected ArrayList<Boolean> subFiltersIncludedCell;
041
042  public FilterListBase(List<Filter> filters) {
043    reversed = checkAndGetReversed(filters, reversed);
044    this.filters = new ArrayList<>(filters);
045  }
046
047  protected static boolean isInReturnCodes(ReturnCode testRC, ReturnCode... returnCodes) {
048    for (ReturnCode rc : returnCodes) {
049      if (testRC == rc) {
050        return true;
051      }
052    }
053    return false;
054  }
055
056  protected static boolean checkAndGetReversed(List<Filter> rowFilters, boolean defaultValue) {
057    if (rowFilters.isEmpty()) {
058      return defaultValue;
059    }
060    boolean retValue = rowFilters.get(0).isReversed();
061    for (int i = 1, n = rowFilters.size(); i < n; i++) {
062      if (rowFilters.get(i).isReversed() != retValue) {
063        throw new IllegalArgumentException("Filters in the list must have the same reversed flag");
064      }
065    }
066    return retValue;
067  }
068
069  public abstract void addFilterLists(List<Filter> filters);
070
071  public int size() {
072    return this.filters.size();
073  }
074
075  public boolean isEmpty() {
076    return this.filters.isEmpty();
077  }
078
079  public ArrayList<Filter> getFilters() {
080    return this.filters;
081  }
082
083  protected int compareCell(Cell a, Cell b) {
084    int cmp = CellComparator.getInstance().compare(a, b);
085    return reversed ? -1 * cmp : cmp;
086  }
087
088  /**
089   * For FilterList, we can consider a filter list as a node in a tree. sub-filters of the filter
090   * list are children of the relative node. The logic of transforming cell of a filter list, well,
091   * we can consider it as the process of post-order tree traverse. For a node , before we traverse
092   * the current child, we should set the traverse result (transformed cell) of previous node(s) as
093   * the initial value. (HBASE-18879).
094   * @param c The cell in question.
095   * @return the transformed cell. n
096   */
097  @Override
098  public Cell transformCell(Cell c) throws IOException {
099    if (isEmpty()) {
100      return super.transformCell(c);
101    }
102    Cell transformed = c;
103    for (int i = 0, n = filters.size(); i < n; i++) {
104      if (subFiltersIncludedCell.get(i)) {
105        transformed = filters.get(i).transformCell(transformed);
106      }
107    }
108    return transformed;
109  }
110
111  /**
112   * Filters that never filter by modifying the returned List of Cells can inherit this
113   * implementation that does nothing. {@inheritDoc}
114   */
115  @Override
116  public void filterRowCells(List<Cell> cells) throws IOException {
117    for (int i = 0, n = filters.size(); i < n; i++) {
118      filters.get(i).filterRowCells(cells);
119    }
120  }
121
122  @Override
123  public boolean hasFilterRow() {
124    for (int i = 0, n = filters.size(); i < n; i++) {
125      if (filters.get(i).hasFilterRow()) {
126        return true;
127      }
128    }
129    return false;
130  }
131
132  @Override
133  public boolean isFamilyEssential(byte[] name) throws IOException {
134    if (this.filters.isEmpty()) {
135      return super.isFamilyEssential(name);
136    }
137    for (int i = 0, n = filters.size(); i < n; i++) {
138      if (filters.get(i).isFamilyEssential(name)) {
139        return true;
140      }
141    }
142    return false;
143  }
144
145  @Override
146  public void setReversed(boolean reversed) {
147    for (int i = 0, n = filters.size(); i < n; i++) {
148      filters.get(i).setReversed(reversed);
149    }
150    this.reversed = reversed;
151  }
152
153  @Override
154  public String toString() {
155    int endIndex = this.size() < MAX_LOG_FILTERS ? this.size() : MAX_LOG_FILTERS;
156    return formatLogFilters(filters.subList(0, endIndex));
157  }
158
159  protected abstract String formatLogFilters(List<Filter> logFilters);
160}