@Override
  protected List<Segment> getSegments() throws IOException {
    List<Segment> list = new ArrayList<>(2);
    list.add(getActive());
    list.add(snapshot);
    return list;
  }
This method is protected under {@link HStore#lock} read lock. <br/>
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hbase-server/src/main/java/org/apache/hadoop/hbase/regionserver/DefaultMemStore.java