Package com.inductiveautomation.ignition.common

Interface StreamingDatasetWriter

All Known Implementing Classes:
BasicStreamingDataset, FilteredStreamingDatasetWriter, StreamingDataset, StreamingDatasetJsonWriter
public interface StreamingDatasetWriter

  • Method Summary

    Modifier and Type
    Method
    Description
    void
    finish()
    Notifies the writer to close- all data has been written.
    void
    finishWithError(Exception e)
    Finishes the stream while indicating an error occurred.
    void
    initialize(String[] columnNames, Class<?>[] columnTypes, boolean supportsQuality, int expectedRows)
    Initializes the streaming dataset with important information, primarily the column names and types.
    void
    write(Object[] data, QualityCode[] quality)
    Writes a row of data to the dataset.

  • Method Details

    • initialize

      void initialize(String[] columnNames, Class<?>[] columnTypes, boolean supportsQuality, int expectedRows)
      Initializes the streaming dataset with important information, primarily the column names and types. If supportsQuality is true, it is expected that every value added has an associated quality. expectedRows gives an idea as to how many rows will be returned- useful for progress indication. Should be -1 if the number cannot be known in advance.
      Parameters:
      columnNames - The names of the columns in the dataset.
      columnTypes - The types of the columns in the dataset.
      supportsQuality - Whether or not the dataset supports quality codes.
      expectedRows - -1 if not known, otherwise the number of rows that will be in the dataset.

    • write

      void write(Object[] data, QualityCode[] quality) throws Exception
      Writes a row of data to the dataset. The data and quality arrays must be the same length, and the data array must be the same length as the number of columns in the dataset.
      Parameters:
      data - The data to write to the dataset.
      quality - The quality codes for the data.
      Throws:
      Exception

    • finish

      void finish()
      Notifies the writer to close- all data has been written. Should be called from a finally block.

    • finishWithError

      void finishWithError(Exception e)
      Finishes the stream while indicating an error occurred. Either this, or the successful finish(), must be called.
      Parameters:
      e - The exception that occurred.