public boolean isRegionCloseMarker() {
    return isMetaEdit() && PrivateCellUtil.matchingQualifier(this.cells.get(0), REGION_EVENT_CLOSE,
      0, REGION_EVENT_CLOSE.length);
  }
Public so can be accessed from regionserver.wal package.
@return True if this is a Marker Edit and it is a RegionClose type.
hbase-server/src/main/java/org/apache/hadoop/hbase/wal/WALEdit.java