code: def export_batch_from_json(self, json_path, num_batch, c_array_ptr):
      json_file = self.java_io.File(json_path)
      with self.java_arrow.vector.ipc.JsonFileReader(
          json_file, self.java_allocator
      ) as json_reader:
          json_reader.start()
          if num_batch > 0:
              actually_skipped = json_reader.skip(num_batch)
              assert actually_skipped == num_batch
          with json_reader.read() as batch:
              dict_provider = json_reader
              self.java_arrow.c.Data.exportVectorSchemaRoot(
                  self.java_allocator,
                  batch,
                  dict_provider,
                  self._wrap_c_array_ptr(c_array_ptr),
              )
  
imports: import contextlib
  import functools
  import os
  import subprocess
  from .None import cdata
  from .tester import Tester, CDataExporter, CDataImporter
  from .util import run_cmd, log
  from ..utils.source import ARROW_ROOT_DEFAULT
label_desc: Use image node_id 2 for calling the JavaCDataExporter obj's underlying member method code with example usage: obj.export_batch_from_json(json_path, num_batch, c_array_ptr) without return types