public Pair<Integer, Integer> getReopenStatus(TableName tableName) {
    if (isTableDisabled(tableName)) {
      return new Pair<Integer, Integer>(0, 0);
    }

    final List<RegionState> states = regionStates.getTableRegionStates(tableName);
    int ritCount = 0;
    for (RegionState regionState : states) {
      if (!regionState.isOpened() && !regionState.isSplit()) {
        ritCount++;
      }
    }
    return new Pair<Integer, Integer>(ritCount, states.size());
  }
Used by the client (via master) to identify if all regions have the schema updates
@return Pair indicating the status of the alter command (pending/total)
hbase-server/src/main/java/org/apache/hadoop/hbase/master/assignment/AssignmentManager.java