flink-python/pyflink/table/sources.py

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from pyflink.java_gateway import get_gateway
from pyflink.table.types import DataType, _to_java_type
from pyflink.util import utils

__all__ = ['TableSource', 'CsvTableSource']


class TableSource(object):
    """
    Defines a table from an external system or location.
    """

    def __init__(self, j_table_source):
        self._j_table_source = j_table_source


class CsvTableSource(TableSource):
    """
    A :class:`TableSource` for simple CSV files with a
    (logically) unlimited number of fields.

    :param source_path: The path to the CSV file.
    :param field_names: The names of the table fields.
    :param field_types: The types of the table fields.
    """

    def __init__(self, source_path, field_names, field_types):
        # type: (str, list[str], list[DataType]) -> None
        gateway = get_gateway()
        j_field_names = utils.to_jarray(gateway.jvm.String, field_names)
        j_field_types = utils.to_jarray(gateway.jvm.TypeInformation,
                                        [_to_java_type(field_type)
                                         for field_type in field_types])
        super(CsvTableSource, self).__init__(
            gateway.jvm.CsvTableSource(source_path, j_field_names, j_field_types))