public void preSplitAfterMETAAction(final User user) throws IOException {
    execOperation(coprocEnvironments.isEmpty() ? null : new MasterObserverOperation(user) {
      @Override
      public void call(MasterObserver observer) throws IOException {
        observer.preSplitRegionAfterMETAAction(this);
      }
    });
  }
This will be called after update META step as part of split table region procedure.
@param user the user
hbase-server/src/main/java/org/apache/hadoop/hbase/master/MasterCoprocessorHost.java