com.prosysopc.ua

Interface AggregateCalculator.HistoryDataProvider

Enclosing class:

AggregateCalculator

public static interface AggregateCalculator.HistoryDataProvider

Method Summary

Modifier and Type	Method and Description
DataValue	readFirstAfterTimestamp(DateTime timeStamp, boolean includeValueAtTimestamp) Get the first DataValue after the given timestamp.
DataValue	readFirstBeforeTimestamp(DateTime timeStamp, boolean includeValueAtTimestamp) Get the first DataValue before the given timestamp.
List<DataValue>	readRawAll(DateTime startTime, DateTime endTime, boolean returnStartBound, boolean returnEndBound) Get all the values from the history that are between startTime and endTime.

Method Detail

readFirstAfterTimestamp

DataValue readFirstAfterTimestamp(DateTime timeStamp,
                                  boolean includeValueAtTimestamp)

Get the first DataValue after the given timestamp. Return null if there is no DataValue after the timestamp.

Parameters:

timeStamp - the SourceTimestamp after which the DataValue is searched for.

includeValueAtTimestamp - specifies if a value on the timestamp can be returned

Returns:

the requested DataValue or null if DataValue does not exist

readFirstBeforeTimestamp

DataValue readFirstBeforeTimestamp(DateTime timeStamp,
                                   boolean includeValueAtTimestamp)

Get the first DataValue before the given timestamp. Return null if there is no DataValue before the timestamp.

Parameters:

timeStamp - the SourceTimestamp before which the DataValue is searched for

includeValueAtTimestamp - specifies if a value on the timestamp can be returned

Returns:

the requested DataValue or null if DataValue does not exist

readRawAll

List<DataValue> readRawAll(DateTime startTime,
                           DateTime endTime,
                           boolean returnStartBound,
                           boolean returnEndBound)
                    throws StatusException

Get all the values from the history that are between startTime and endTime. THe function does not return continuation points but instead returns a StatusException in case the request cannot be completed in one call.

Parameters:

startTime - the start of the interval

endTime - the end of the interval

returnStartBound - whether a value at the start of the interval should be returned as well

returnEndBound - whether a value at the end of the interval should be returned as well

Returns:

a list of the requested DataValues

Throws:

StatusException