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 static org.junit.Assert.assertArrayEquals;
021
022import java.io.IOException;
023import java.util.ArrayList;
024import java.util.List;
025import org.apache.hadoop.conf.Configuration;
026import org.apache.hadoop.hbase.Cell;
027import org.apache.hadoop.hbase.CellUtil;
028import org.apache.hadoop.hbase.HBaseClassTestRule;
029import org.apache.hadoop.hbase.HBaseTestingUtil;
030import org.apache.hadoop.hbase.HConstants;
031import org.apache.hadoop.hbase.PrivateCellUtil;
032import org.apache.hadoop.hbase.TableName;
033import org.apache.hadoop.hbase.client.Put;
034import org.apache.hadoop.hbase.client.Result;
035import org.apache.hadoop.hbase.client.ResultScanner;
036import org.apache.hadoop.hbase.client.Scan;
037import org.apache.hadoop.hbase.client.Table;
038import org.apache.hadoop.hbase.exceptions.DeserializationException;
039import org.apache.hadoop.hbase.regionserver.ConstantSizeRegionSplitPolicy;
040import org.apache.hadoop.hbase.testclassification.FilterTests;
041import org.apache.hadoop.hbase.testclassification.MediumTests;
042import org.apache.hadoop.hbase.util.Bytes;
043import org.junit.AfterClass;
044import org.junit.BeforeClass;
045import org.junit.ClassRule;
046import org.junit.Rule;
047import org.junit.Test;
048import org.junit.experimental.categories.Category;
049import org.junit.rules.TestName;
050
051@Category({ FilterTests.class, MediumTests.class })
052public class TestSeekHints {
053
054  private final static HBaseTestingUtil TEST_UTIL = new HBaseTestingUtil();
055  private static String cf = "f";
056  private static String cq = "q";
057  private static String table = "t";
058  private static Table ht;
059
060  @ClassRule
061  public static final HBaseClassTestRule CLASS_RULE =
062    HBaseClassTestRule.forClass(TestSeekHints.class);
063
064  @Rule
065  public TestName name = new TestName();
066
067  @BeforeClass
068  public static void setUpBeforeClass() throws Exception {
069    Configuration conf = TEST_UTIL.getConfiguration();
070    conf.setInt("hbase.client.scanner.caching", 1000);
071    conf.set(HConstants.HBASE_REGION_SPLIT_POLICY_KEY,
072      ConstantSizeRegionSplitPolicy.class.getName());
073    // set no splits
074    conf.setLong(HConstants.HREGION_MAX_FILESIZE, (1024L) * 1024 * 1024 * 10);
075
076    TEST_UTIL.startMiniCluster();
077
078    // load the mini cluster with a single table with 20 rows, with rowkeys of a single byte, 0-19.
079    ht = TEST_UTIL.createTable(TableName.valueOf(table), Bytes.toBytes(cf), Integer.MAX_VALUE);
080    for (byte b = 0; b < 20; b++) {
081      Put put = new Put(new byte[] { b }).addColumn(Bytes.toBytes(cf), Bytes.toBytes(cq),
082        Bytes.toBytes("value"));
083      ht.put(put);
084    }
085    TEST_UTIL.flush();
086  }
087
088  @AfterClass
089  public static void tearDownAfterClass() throws Exception {
090    TEST_UTIL.shutdownMiniCluster();
091  }
092
093  @Test
094  public void testNormalScanForwardsSeek() throws IOException {
095
096    KeepAllButSeekFilter filter = new KeepAllButSeekFilter((byte) 10, (byte) 15);
097
098    Scan scan = new Scan();
099    scan.setFilter(filter);
100
101    ResultScanner scanner = ht.getScanner(scan);
102    List<byte[]> actualRowsList = new ArrayList<>();
103    for (Result result : scanner) {
104      actualRowsList.add(result.getRow());
105    }
106    byte[][] actualRows = actualRowsList.toArray(new byte[][] {});
107
108    List<byte[]> expectedRowsList = new ArrayList<>();
109    // Start counting up from 0, as that's the first of our test rows
110    for (byte i = 0; i < 10; i++) {
111      expectedRowsList.add(new byte[] { i });
112    }
113    // Skip rows starting from 10 and ending before 15, as the filter should remove them
114    for (byte i = 15; i < 20; i++) {
115      expectedRowsList.add(new byte[] { i });
116    }
117    byte[][] expectedRows = expectedRowsList.toArray(new byte[][] {});
118
119    assertArrayEquals(expectedRows, actualRows);
120  }
121
122  @Test
123  public void testReversedScanBackwardsSeek() throws IOException {
124
125    KeepAllButSeekFilter filter = new KeepAllButSeekFilter((byte) 10, (byte) 5);
126
127    Scan scan = new Scan();
128    scan.setFilter(filter);
129    scan.setReversed(true);
130
131    ResultScanner scanner = ht.getScanner(scan);
132    List<byte[]> actualRowsList = new ArrayList<>();
133    for (Result result : scanner) {
134      actualRowsList.add(result.getRow());
135    }
136    byte[][] actualRows = actualRowsList.toArray(new byte[][] {});
137
138    List<byte[]> expectedRowsList = new ArrayList<>();
139    // Start counting down from 19, as that's the last of our test rows
140    for (byte i = 19; i > 10; i--) {
141      expectedRowsList.add(new byte[] { i });
142    }
143    // Skip rows starting from 10 and ending before 5, as the filter should remove them
144    for (byte i = 5; i >= 0; i--) {
145      expectedRowsList.add(new byte[] { i });
146    }
147    byte[][] expectedRows = expectedRowsList.toArray(new byte[][] {});
148
149    assertArrayEquals(expectedRows, actualRows);
150  }
151
152  public static class KeepAllButSeekFilter extends FilterBase {
153
154    private byte seekStartRow;
155    private byte seekTargetRow;
156
157    public KeepAllButSeekFilter(byte seekStartRow, byte seekTargetRow) {
158      this.seekStartRow = seekStartRow;
159      this.seekTargetRow = seekTargetRow;
160    }
161
162    /*
163     * We return SEEK_NEXT_USING_HINT when we hit the specified row, but we return INCLUDE for all
164     * other rows. This will wind up including the rows between our "seek" row and our "hint" row
165     * only if we don't seek past them.
166     */
167    @Override
168    public ReturnCode filterCell(final Cell c) throws IOException {
169      byte rowKeyPrefix = CellUtil.cloneRow(c)[0];
170      if (rowKeyPrefix == seekStartRow) {
171        return ReturnCode.SEEK_NEXT_USING_HINT;
172      }
173      return ReturnCode.INCLUDE;
174    }
175
176    @Override
177    public Cell getNextCellHint(Cell currentCell) {
178      return PrivateCellUtil.createFirstOnRow(new byte[] { seekTargetRow });
179    }
180
181    @Override
182    public byte[] toByteArray() {
183      return new byte[] { seekStartRow, seekTargetRow };
184    }
185
186    public static KeepAllButSeekFilter parseFrom(final byte[] pbBytes)
187      throws DeserializationException {
188
189      return new KeepAllButSeekFilter(pbBytes[0], pbBytes[1]);
190    }
191  }
192
193}