void initializeStreaming(Configuration cfg, boolean isMapSide) throws HiveException {
      PartitionedTableFunctionDef tabDef = tabFn.getTableDef();
      PTFInputDef inputDef = tabDef.getInput();
      ObjectInspector inputOI = conf.getStartOfChain() == tabDef ?
          inputObjInspectors[0] : inputDef.getOutputShape().getOI();

      tabFn.initializeStreaming(cfg, (StructObjectInspector) inputOI, isMapSide);

      if ( next != null ) {
        next.initializeStreaming(cfg, isMapSide);
      }
    }
@return the name of the operator
ql/src/java/org/apache/hadoop/hive/ql/exec/PTFOperator.java