@Override
  public byte[] generateValue(byte[] rowKey, byte[] cf, byte[] column) {
    if (Arrays.equals(cf, mobColumnFamily))
      return mobKvGenerator.generateRandomSizeValue(rowKey, cf, column);

    return super.generateValue(rowKey, cf, column);
  }
A load test data generator for MOB
hbase-diagnostics/src/main/java/org/apache/hadoop/hbase/util/LoadTestDataGeneratorWithMOB.java