de.alpharogroup.model

Class LoadableDetachableModel<T>

java.lang.Object

de.alpharogroup.model.LoadableDetachableModel<T>

Type Parameters:

T - The Model Object type

All Implemented Interfaces:

de.alpharogroup.model.api.Attachable, de.alpharogroup.model.api.Detachable, de.alpharogroup.model.api.Model<T>, Serializable

public abstract class LoadableDetachableModel<T>
extends Object
implements de.alpharogroup.model.api.Model<T>

Model that makes working with detachable models a breeze. LoadableDetachableModel holds a temporary, transient model object, that is set when getObject() is called by calling abstract method 'load', and that will be reset/ set to null on detach(). A usage example:

 LoadableDetachableModel venueListModel = new LoadableDetachableModel()
 {
        protected Object load()
        {
                return getVenueDao().findVenues();
        }
 };
 

Though you can override methods onAttach() and onDetach() for additional attach/ detach behavior, the point of this class is to hide as much of the attaching/ detaching as possible. So you should rarely need to override those methods, if ever.

Author:

Eelco Hillenius, Igor Vaynberg

See Also:

Serialized Form

Constructor Summary

Constructors

Constructor and Description
LoadableDetachableModel(T object) This constructor is used if you already have the object retrieved and want to wrap it with a detachable model.

Method Summary

Modifier and Type	Method and Description
void	detach()
T	getObject()
boolean	isAttached() Checks if the object is attached.
protected abstract T	load() Loads and returns the (temporary) model object.
protected void	onAttach() Attaches to the current request.
protected void	onDetach() Detaches from the current request.
void	setObject(T object) Manually loads the model with the specified object.
String	toString()

Methods inherited from class java.lang.Object

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

Methods inherited from interface de.alpharogroup.model.api.Attachable

attach

Constructor Detail

LoadableDetachableModel

public LoadableDetachableModel(T object)

This constructor is used if you already have the object retrieved and want to wrap it with a detachable model.

Parameters:

object - retrieved instance of the detachable object

Method Detail

detach

public void detach()

Specified by:

detach in interface de.alpharogroup.model.api.Detachable

getObject

public final T getObject()

Specified by:

getObject in interface de.alpharogroup.model.api.Model<T>

isAttached

public final boolean isAttached()

Checks if the object is attached.

Returns:

true, if the object is attached otherwise false

load

protected abstract T load()

Loads and returns the (temporary) model object.

Returns:

the (temporary) model object

onAttach

protected void onAttach()

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

onDetach

protected void onDetach()

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

setObject

public void setObject(T object)

Manually loads the model with the specified object. Subsequent calls to getObject() will return object until detach() is called.

Specified by:

setObject in interface de.alpharogroup.model.api.Model<T>

Parameters:

object - The object to set into the model

toString

public String toString()

Overrides:

toString in class Object