@Override
  public List<StatusJournalEntry> getStatusJournal() {
    if (journal == null) {
      return Collections.emptyList();
    } else {
      return ImmutableList.copyOf(journal);
    }
  }
Returns the status journal. This implementation of status journal is not thread-safe. Currently
we use this to track various stages of flushes and compactions where we can use this/pretty
print for post task analysis, by which time we are already done changing states (writing to
journal)
hbase-server/src/main/java/org/apache/hadoop/hbase/monitoring/MonitoredTaskImpl.java