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1   /**
2    * Licensed to the Apache Software Foundation (ASF) under one
3    * or more contributor license agreements.  See the NOTICE file
4    * distributed with this work for additional information
5    * regarding copyright ownership.  The ASF licenses this file
6    * to you under the Apache License, Version 2.0 (the
7    * "License"); you may not use this file except in compliance
8    * with the License.  You may obtain a copy of the License at
9    *
10   *     http://www.apache.org/licenses/LICENSE-2.0
11   *
12   * Unless required by applicable law or agreed to in writing, software
13   * distributed under the License is distributed on an "AS IS" BASIS,
14   * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
15   * See the License for the specific language governing permissions and
16   * limitations under the License.
17   */
18  package org.apache.hadoop.hbase.replication;
19  
20  import java.util.UUID;
21  import org.apache.hadoop.hbase.Cell;
22  import org.apache.hadoop.hbase.CellUtil;
23  import org.apache.hadoop.hbase.classification.InterfaceAudience;
24  import org.apache.hadoop.hbase.wal.WAL;
25  
26  /**
27   * A dummy {@link ReplicationEndpoint} that replicates nothing.
28   * <p/>
29   * Mainly used by ITBLL to check whether all the entries in WAL files are fine, since for normal
30   * case, we will only read the WAL files when there are region servers crash and we need to split
31   * the log, but for replication we will read all the entries and pass them to the
32   * {@link ReplicationEndpoint}, so setting up a replication peer can help finding out whether there
33   * are broken entries in WAL files.
34   */
35  @InterfaceAudience.Private
36  public class VerifyWALEntriesReplicationEndpoint extends BaseReplicationEndpoint {
37  
38    @Override
39    public boolean canReplicateToSameCluster() {
40      return true;
41    }
42  
43    @Override
44    public UUID getPeerUUID() {
45      return ctx.getClusterId();
46    }
47  
48    @Override
49    public WALEntryFilter getWALEntryfilter() {
50      return null;
51    }
52  
53    private void checkCell(Cell cell) {
54      // check whether all the fields are fine
55      CellUtil.cloneRow(cell);
56      CellUtil.cloneFamily(cell);
57      CellUtil.cloneQualifier(cell);
58      CellUtil.cloneValue(cell);
59    }
60  
61    @Override
62    public boolean replicate(ReplicateContext replicateContext) {
63      for (WAL.Entry entry : replicateContext.getEntries()) {
64        for (Cell cell: entry.getEdit().getCells()) {
65          checkCell(cell);
66        }
67      }
68      return true;
69    }
70  
71    @Override
72    protected void doStart() {
73      notifyStarted();
74    }
75  
76    @Override
77    protected void doStop() {
78      notifyStopped();
79    }
80  }