paimon-python/pypaimon/table/row/internal_row.py

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from abc import ABC, abstractmethod
from typing import Any

from pypaimon.table.row.row_kind import RowKind


class InternalRow(ABC):
    """
    Base interface for an internal data structure representing data of RowType.
    """

    @abstractmethod
    def get_field(self, pos: int) -> Any:
        """
        Returns the value at the given position.
        """

    @abstractmethod
    def get_row_kind(self) -> RowKind:
        """
        Returns the kind of change that this row describes in a changelog.
        """

    @abstractmethod
    def __len__(self) -> int:
        """
        Returns the number of fields in this row.
        The number does not include RowKind. It is kept separately.
        """

    def __str__(self) -> str:
        fields = []
        for pos in range(self.__len__()):
            value = self.get_field(pos)
            fields.append(str(value))
        return " ".join(fields)