private ObjectInspector getArrayWritableObjectInspector(final String columnTypes) {
    List<TypeInfo> columnTypeList = TypeInfoUtils.getTypeInfosFromTypeString(columnTypes);
    List<String> columnNameList = Arrays.asList(getColumnNames(columnTypes).split(","));
    StructTypeInfo rowTypeInfo = (StructTypeInfo)TypeInfoFactory.getStructTypeInfo(columnNameList, columnTypeList);

    return new ArrayWritableObjectInspector(rowTypeInfo);
  }
We use LazySimpleSerDe to generate our testing rows.
itests/hive-jmh/src/main/java/org/apache/hive/benchmark/storage/ColumnarStorageBench.java