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.regionserver.wal;
019
020import java.io.IOException;
021import java.util.Collections;
022import java.util.List;
023import java.util.Set;
024import java.util.TreeSet;
025import org.apache.hadoop.hbase.Cell;
026import org.apache.hadoop.hbase.CellUtil;
027import org.apache.hadoop.hbase.PrivateCellUtil;
028import org.apache.hadoop.hbase.client.RegionInfo;
029import org.apache.hadoop.hbase.ipc.ServerCall;
030import org.apache.hadoop.hbase.regionserver.MultiVersionConcurrencyControl;
031import org.apache.hadoop.hbase.util.Bytes;
032import org.apache.hadoop.hbase.wal.WAL.Entry;
033import org.apache.hadoop.hbase.wal.WALEdit;
034import org.apache.hadoop.hbase.wal.WALKeyImpl;
035import org.apache.yetus.audience.InterfaceAudience;
036
037import org.apache.hbase.thirdparty.org.apache.commons.collections4.CollectionUtils;
038
039/**
040 * A WAL Entry for {@link AbstractFSWAL} implementation. Immutable. A subclass of {@link Entry} that
041 * carries extra info across the ring buffer such as region sequenceid (we want to use this later,
042 * just before we write the WAL to ensure region edits maintain order). The extra info added here is
043 * not 'serialized' as part of the WALEdit hence marked 'transient' to underline this fact. It also
044 * adds mechanism so we can wait on the assign of the region sequence id. See
045 * #stampRegionSequenceId().
046 */
047@InterfaceAudience.Private
048class FSWALEntry extends Entry {
049  // The below data members are denoted 'transient' just to highlight these are not persisted;
050  // they are only in memory and held here while passing over the ring buffer.
051  private final transient long txid;
052
053  /**
054   * If false, means this is a meta edit written by the hbase system itself. It was not in memstore.
055   * HBase uses these edit types to note in the log operational transitions such as compactions,
056   * flushes, or region open/closes.
057   */
058  private final transient boolean inMemstore;
059
060  /**
061   * Set if this is a meta edit and it is of close region type.
062   */
063  private final transient boolean closeRegion;
064
065  private final transient RegionInfo regionInfo;
066  private final transient Set<byte[]> familyNames;
067  private final transient ServerCall<?> rpcCall;
068
069  /**
070   * @param inMemstore If true, then this is a data edit, one that came from client. If false, it is
071   *                   a meta edit made by the hbase system itself and is for the WAL only.
072   */
073  FSWALEntry(final long txid, final WALKeyImpl key, final WALEdit edit, final RegionInfo regionInfo,
074    final boolean inMemstore, ServerCall<?> rpcCall) {
075    super(key, edit);
076    this.inMemstore = inMemstore;
077    this.closeRegion = !inMemstore && edit.isRegionCloseMarker();
078    this.regionInfo = regionInfo;
079    this.txid = txid;
080    if (inMemstore) {
081      // construct familyNames here to reduce the work of log sinker.
082      Set<byte[]> families = edit.getFamilies();
083      this.familyNames = families != null ? families : collectFamilies(edit.getCells());
084    } else {
085      this.familyNames = Collections.emptySet();
086    }
087    this.rpcCall = rpcCall;
088    if (rpcCall != null) {
089      rpcCall.retainByWAL();
090    }
091  }
092
093  static Set<byte[]> collectFamilies(List<Cell> cells) {
094    if (CollectionUtils.isEmpty(cells)) {
095      return Collections.emptySet();
096    } else {
097      Set<byte[]> set = new TreeSet<>(Bytes.BYTES_COMPARATOR);
098      for (Cell cell : cells) {
099        if (!WALEdit.isMetaEditFamily(cell)) {
100          set.add(CellUtil.cloneFamily(cell));
101        }
102      }
103      return set;
104    }
105  }
106
107  @Override
108  public String toString() {
109    return "sequence=" + this.txid + ", " + super.toString();
110  }
111
112  boolean isInMemStore() {
113    return this.inMemstore;
114  }
115
116  boolean isCloseRegion() {
117    return closeRegion;
118  }
119
120  RegionInfo getRegionInfo() {
121    return this.regionInfo;
122  }
123
124  /** Returns The transaction id of this edit. */
125  long getTxid() {
126    return this.txid;
127  }
128
129  /**
130   * Here is where a WAL edit gets its sequenceid. SIDE-EFFECT is our stamping the sequenceid into
131   * every Cell AND setting the sequenceid into the MVCC WriteEntry!!!!
132   * @return The sequenceid we stamped on this edit.
133   */
134  long stampRegionSequenceId(MultiVersionConcurrencyControl.WriteEntry we) throws IOException {
135    long regionSequenceId = we.getWriteNumber();
136    if (!this.getEdit().isReplay() && inMemstore) {
137      for (Cell c : getEdit().getCells()) {
138        PrivateCellUtil.setSequenceId(c, regionSequenceId);
139      }
140    }
141
142    getKey().setWriteEntry(we);
143    return regionSequenceId;
144  }
145
146  /** Returns the family names which are effected by this edit. */
147  Set<byte[]> getFamilyNames() {
148    return familyNames;
149  }
150
151  void release() {
152    if (rpcCall != null) {
153      rpcCall.releaseByWAL();
154    }
155  }
156}