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 with the given data.

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:

expectedRows - -1 if not known, otherwise the number of rows that will be in the dataset.

write

void write(Object[] data,
 QualityCode[] quality)
    throws IOException

Writes a row with the given data. Bounds and order of arrays must match that used to call initialize. quality may be null if dataset does not support quality.

Throws:

IOException

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.