wicket.model
Class AbstractDetachableModel

java.lang.Object
  wicket.model.AbstractDetachableModel

All Implemented Interfaces:

IDetachable, IModel, java.io.Serializable

Direct Known Subclasses:

AbstractPropertyModel, AbstractReadOnlyDetachableModel, FeedbackMessagesModel, ListItemModel, LoadableDetachableModel

public abstract class AbstractDetachableModel

extends java.lang.Object

implements IModel

This provide a base class to work with detachable IModels. It encapsulates the logic for attaching and detaching models. The onAttach() abstract method will be called at the first access to the model within a request and - if the model was attached earlier, onDetach() will be called at the end of the request. In effect, attachment and detachment is only done when it is actually needed.

Author:

Chris Turner, Eelco Hillenius, Jonathan Locke

See Also:

Serialized Form

Constructor Summary

AbstractDetachableModel()

Method Summary

void	attach() Attaches the model.
void	detach() Detaches model after use.
abstract IModel	getNestedModel() Gets the nested model.
java.lang.Object	getObject(Component component) Gets the model object.
boolean	isAttached() Gets whether this model has been attached to the current session.
protected abstract void	onAttach() Attaches to the current request.
protected abstract void	onDetach() Detaches from the current request.
protected abstract java.lang.Object	onGetObject(Component component) Called when getObject is called in order to retrieve the detachable object.
protected abstract void	onSetObject(Component component, java.lang.Object object) Called when setObject is called in order to change the detachable object.
void	setObject(Component component, java.lang.Object object) Sets the model object.
java.lang.String	toString()

Methods inherited from class java.lang.Object

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

Constructor Detail

AbstractDetachableModel

public AbstractDetachableModel()

Method Detail

attach

public final void attach()

Attaches the model.

detach

public final void detach()

Description copied from interface: IDetachable

Detaches model after use. This is generally used to null out transient references that can be re-attached later.

Specified by:

detach in interface IDetachable

See Also:

IDetachable.detach()

getNestedModel

public abstract IModel getNestedModel()

Description copied from interface: IModel

Gets the nested model.

Specified by:

getNestedModel in interface IModel

Returns:

The nested model object.

See Also:

IModel.getNestedModel()

getObject

public final java.lang.Object getObject(Component component)

Description copied from interface: IModel

Gets the model object.

Specified by:

getObject in interface IModel

Parameters:

component - The component which wants to get a model Object

Returns:

The model object

See Also:

IModel.getObject(Component)

isAttached

public boolean isAttached()

Gets whether this model has been attached to the current session.

Returns:

whether this model has been attached to the current session

setObject

public final void setObject(Component component,
                            java.lang.Object object)

Description copied from interface: IModel

Sets the model object.

Specified by:

setObject in interface IModel

Parameters:

component - The component which wants to set a new model Object

object - The model object

See Also:

IModel.setObject(Component, Object)

toString

public java.lang.String toString()

See Also:

Object.toString()

onAttach

protected abstract void onAttach()

Attaches to the current request. Implement this method with custom behaviour, such as loading the model object.

onDetach

protected abstract void onDetach()

Detaches from the current request. Implement this method with custom behaviour, such as setting the model object to null.

onGetObject

protected abstract java.lang.Object onGetObject(Component component)

Called when getObject is called in order to retrieve the detachable object. Before this method is called, getObject() always calls attach() to ensure that the object is attached.

Parameters:

component - The component asking for the object

Returns:

The object

onSetObject

protected abstract void onSetObject(Component component,
                                    java.lang.Object object)

Called when setObject is called in order to change the detachable object. Before this method is called, setObject() always calls attach() to ensure that the object is attached.

Parameters:

component - The component asking for replacement of the model object

object - The new model object