org.eclipse.scada.da.server.common.exporter

Class ObjectExporter

java.lang.Object

org.eclipse.scada.da.server.common.exporter.AbstractObjectExporter

org.eclipse.scada.da.server.common.exporter.ObjectExporter

All Implemented Interfaces:

PropertyChangeListener, EventListener, Disposable

public class ObjectExporter
extends AbstractObjectExporter
implements PropertyChangeListener, Disposable

An object exporter which will bind to the change events of a bean.

The object exporter is attached to a bean using attachTarget(Object) and reads out the initial state of the bean and tries to subscribe to the bean using the method addPropertyChangeListener. Changes announced by the bean will then be reflected in the data items of the exporter.

The difference to the StaticObjectExporter is, that the bean class type must not be known in advance and data items will be created on the fly based on the provided target object. If the target bean does not provide the addPropertyChangeListener method it still shows the state the target bean had on attaching but will not update. Attaching to a new target object is more expensive using the ObjectExporter since all data items will be destroyed in the process.

Field Summary

Fields inherited from class org.eclipse.scada.da.server.common.exporter.AbstractObjectExporter

attributes, factory, items

Constructor Summary

Constructors

Constructor and Description
ObjectExporter(ItemFactory itemFactory) Create a new object exporter
ObjectExporter(ItemFactory itemFactory, boolean readOnly, boolean nullIsError) Create a new object exporter
ObjectExporter(ItemFactory itemFactory, boolean readOnly, boolean nullIsError, String prefix) Create a new object exporter

Method Summary

Methods

Modifier and Type	Method and Description
void	attachTarget(Object target) attach a new target.
void	detachTarget() detach from the current target if we have one
void	dispose()
protected void	fillAttributes(PropertyDescriptor pd, Map<String,Variant> attributes)
protected Map<String,Variant>	getAdditionalAttributes()
protected Method	getEventMethod(String methodName)
protected Object	getTarget() Get the current target or null if there is none
void	propertyChange(PropertyChangeEvent evt)
void	setAttributes(Map<String,Variant> additionalAttributes)

Methods inherited from class org.eclipse.scada.da.server.common.exporter.AbstractObjectExporter

createDataItems, findAnnotation, getOptions, initAttribute, makeItemName, updateAttribute, updateItemsFromTarget, writeAttribute

Methods inherited from class java.lang.Object

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

Constructor Detail

ObjectExporter

public ObjectExporter(ItemFactory itemFactory)

Create a new object exporter

Parameters:

itemFactory - the factory used to create items. This factory is disposed when the object exporter is disposed.

ObjectExporter

public ObjectExporter(ItemFactory itemFactory,
              boolean readOnly,
              boolean nullIsError,
              String prefix)

Create a new object exporter

Parameters:

itemFactory - the factory used to create items. This factory is disposed when the object exporter is disposed.

readOnly - set to true in order to make all items read-only

nullIsError - set to true to mark fields that are null with an error attribute

prefix - the prefix of the item ids

ObjectExporter

public ObjectExporter(ItemFactory itemFactory,
              boolean readOnly,
              boolean nullIsError)

Create a new object exporter

Parameters:

itemFactory - the factory used to create items. This factory is disposed when the object exporter is disposed.

readOnly - set to true in order to make all items read-only

nullIsError - set to true to mark fields that are null with an error attribute

Method Detail

attachTarget

public void attachTarget(Object target)

attach a new target. the old target will get detached.

Parameters:

target - the new target

setAttributes

public void setAttributes(Map<String,Variant> additionalAttributes)

getAdditionalAttributes

protected Map<String,Variant> getAdditionalAttributes()

Overrides:

getAdditionalAttributes in class AbstractObjectExporter

fillAttributes

protected void fillAttributes(PropertyDescriptor pd,
                  Map<String,Variant> attributes)

Overrides:

fillAttributes in class AbstractObjectExporter

detachTarget

public void detachTarget()

detach from the current target if we have one

dispose

public void dispose()

Specified by:

dispose in interface Disposable

Overrides:

dispose in class AbstractObjectExporter

getEventMethod

protected Method getEventMethod(String methodName)

propertyChange

public void propertyChange(PropertyChangeEvent evt)

Specified by:

propertyChange in interface PropertyChangeListener

getTarget

protected Object getTarget()

Description copied from class: AbstractObjectExporter

Get the current target or null if there is none

Specified by:

getTarget in class AbstractObjectExporter

Returns:

the current target