Package com.inductiveautomation.historian.gateway.api.query

Interface ValuePublisher

All Superinterfaces:

ResultPublisher<ResultNodeDefinition>

All Known Implementing Classes:

HistorianQueryExecutor

public interface ValuePublisher
extends ResultPublisher<ResultNodeDefinition>

Nested Class Summary

Nested classes/interfaces inherited from interface com.inductiveautomation.historian.gateway.api.query.ResultPublisher

ResultPublisher.PublisherState

Method Summary

Modifier and Type	Method	Description
void	initialize(ResultNodeDefinition definition, DataType dataType)	Initializes the publisher with the expected data type.
void	publish(ResultNodeDefinition definition, QualifiedValue value)	Publishes a value for the given query definition.

Methods inherited from interface com.inductiveautomation.historian.gateway.api.query.ResultPublisher

cancel, finish, finishWithError, getIdentifier, getState, initializeWithFailure

Method Details

initialize

void initialize(ResultNodeDefinition definition,
 DataType dataType)
         throws IllegalStateException

Initializes the publisher with the expected data type. This method must be called before any publishing operations.

Parameters:

definition - The query definition

dataType - The class representing the type of data to be published

Throws:

IllegalStateException - if the publisher is not in UNINITIALIZED state

publish

void publish(ResultNodeDefinition definition,
 QualifiedValue value)
      throws IllegalStateException

Publishes a value for the given query definition.

Parameters:

definition - The query definition

value - The value to publish

Throws:

IllegalStateException - if the publisher is not in PUBLISHING state