@Override
  public String prettyPrintJournal() {
    if (journal == null) {
      return "";
    }
    StringBuilder sb = new StringBuilder();
    Iterator<StatusJournalEntry> iter = journal.iterator();
    StatusJournalEntry previousEntry = null;
    while (iter.hasNext()) {
      StatusJournalEntry entry = iter.next();
      sb.append(entry);
      if (previousEntry != null) {
        long delta = entry.getTimeStamp() - previousEntry.getTimeStamp();
        if (delta != 0) {
          sb.append(" (+" + delta + " ms)");
        }
      }
      previousEntry = entry;
    }
    return sb.toString();
  }
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