org.eclipse.scada.da.datasource.item

Class DataItemSourceImpl

java.lang.Object

org.eclipse.scada.da.datasource.base.AbstractDataSource

org.eclipse.scada.da.datasource.item.DataItemSourceImpl

All Implemented Interfaces:

ItemUpdateListener, DataSource

public class DataItemSourceImpl
extends AbstractDataSource
implements ItemUpdateListener

Field Summary

Fields inherited from interface org.eclipse.scada.da.datasource.DataSource

DATA_SOURCE_ID

Constructor Summary

Constructors

Constructor and Description
DataItemSourceImpl(org.osgi.framework.BundleContext context, Executor executor)

Method Summary

Methods

Modifier and Type	Method and Description
void	dispose()
protected Executor	getExecutor() Return the executor to use for sending out events
void	notifyDataChange(Variant value, Map<String,Variant> attributes, boolean cache) A change on the data item occurred.
void	notifySubscriptionChange(SubscriptionState state, Throwable error) Notify a change in the subscription change
protected void	setConnection(ConnectionService connectionService)
NotifyFuture<WriteAttributeResults>	startWriteAttributes(Map<String,Variant> attributes, OperationParameters operationParameters)
NotifyFuture<WriteResult>	startWriteValue(Variant value, OperationParameters operationParameters)
void	update(Map<String,String> parameters)

Methods inherited from class org.eclipse.scada.da.datasource.base.AbstractDataSource

addListener, removeListener, updateData

Methods inherited from class java.lang.Object

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

Constructor Detail

DataItemSourceImpl

public DataItemSourceImpl(org.osgi.framework.BundleContext context,
                  Executor executor)

Method Detail

getExecutor

protected Executor getExecutor()

Description copied from class: AbstractDataSource

Return the executor to use for sending out events

Specified by:

getExecutor in class AbstractDataSource

Returns:

the executor to use, must never be null

dispose

public void dispose()

update

public void update(Map<String,String> parameters)

setConnection

protected void setConnection(ConnectionService connectionService)

notifyDataChange

public void notifyDataChange(Variant value,
                    Map<String,Variant> attributes,
                    boolean cache)

Description copied from interface: ItemUpdateListener

A change on the data item occurred.

Specified by:

notifyDataChange in interface ItemUpdateListener

Parameters:

value - The new value, or null if the value did not change

attributes - The attributes that changed, may be null if no attribute change at all. The must be unmodifiable by the receiver

cache - Indicating that the change came from the cache, this means that the change was not triggered by a device and that all attribute where sent, not only the changed ones

notifySubscriptionChange

public void notifySubscriptionChange(SubscriptionState state,
                            Throwable error)

Description copied from interface: ItemUpdateListener

Notify a change in the subscription change

Specified by:

notifySubscriptionChange in interface ItemUpdateListener

Parameters:

state - the new subscription change

error - the new subscription error or null if everything is ok

startWriteValue

public NotifyFuture<WriteResult> startWriteValue(Variant value,
                                        OperationParameters operationParameters)

Specified by:

startWriteValue in interface DataSource

startWriteAttributes

public NotifyFuture<WriteAttributeResults> startWriteAttributes(Map<String,Variant> attributes,
                                                       OperationParameters operationParameters)

Specified by:

startWriteAttributes in interface DataSource