private WALEdit addCell(ExtendedCell cell) {
    this.cells.add(cell);
    return this;
  }
Append the given map of family-&gt; edits to a WALEdit data structure. This does not write to
the WAL itself. Note that as an optimization, we will stamp the Set of column families into the
WALEdit to save on our having to calculate column families subsequently down in the actual WAL
writing.
@param familyMap map of family -&gt; edits
hbase-server/src/main/java/org/apache/hadoop/hbase/wal/WALEdit.java