Package com.inductiveautomation.historian.gateway.query.writing

Class CalculationHistoryWriter

java.lang.Object

com.inductiveautomation.historian.gateway.query.writing.HistoryWriter

com.inductiveautomation.historian.gateway.query.writing.CalculationHistoryWriter

All Implemented Interfaces:

QueryController

public class CalculationHistoryWriter
extends HistoryWriter

This writer writes in the format "Timestamp, TagPath, Calc1, Calc2, Calc3..."

Nested Class Summary

Nested classes/interfaces inherited from class com.inductiveautomation.historian.gateway.query.writing.HistoryWriter

HistoryWriter.BlockIdGenerator, HistoryWriter.LegacyBlockIdGenerator, HistoryWriter.ListHead, HistoryWriter.ModernBlockIdGenerator

Field Summary

Fields inherited from class com.inductiveautomation.historian.gateway.query.writing.HistoryWriter

colList, columns, log, rowData, rowQuality, scSet

Constructor Summary

Constructors

Constructor	Description
CalculationHistoryWriter(String queryId, StreamingDatasetWriter writer, TagHistoryQueryParams params)

Method Summary

Modifier and Type	Method	Description
protected DataTypeClass	calculateDataType(int calcId)	For a given calculation, looks at each of the column types and returns the most permissive data type.
protected void	commitRows()
protected void	initColumns()	Creates the arrays rowData and rowQuality, which will get filled in, and then written from.
protected void	initializeWriter()

Methods inherited from class com.inductiveautomation.historian.gateway.query.writing.HistoryWriter

advanceBlockEnd, calculateBlockSize, calculateMaxRowLimit, execute, finalizeWriter, getBlockId, getBlockSize, getColumns, getLogger, getQueryEnd, getQueryId, getQueryParameters, getQueryStart, getRowCount, incrementRowCount, initLoader, insertInList, isRawQuery, markCompletedTo, registerColumn, setQueryExecutor, setWriter

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Constructor Details

CalculationHistoryWriter

public CalculationHistoryWriter(String queryId,
 StreamingDatasetWriter writer,
 TagHistoryQueryParams params)

Method Details

initColumns

protected void initColumns()
                    throws Exception

Description copied from class: HistoryWriter

Creates the arrays rowData and rowQuality, which will get filled in, and then written from. If a HistoryWriter subclass returns a set of columns that are different than the natural set, this function should be overridden.

Overrides:

initColumns in class HistoryWriter

Throws:

Exception

calculateDataType

protected DataTypeClass calculateDataType(int calcId)

For a given calculation, looks at each of the column types and returns the most permissive data type.

initializeWriter

protected void initializeWriter()

Overrides:

initializeWriter in class HistoryWriter

commitRows

protected void commitRows()
                   throws Exception

Overrides:

commitRows in class HistoryWriter

Throws:

Exception