org.springframework.binding.value
Interface ValueModel

All Known Subinterfaces:

DerivedValueModel, DirtyTrackingValueModel, IndexAdapter

All Known Implementing Classes:

AbstractDerivedValueModel, AbstractIndexAdapter, AbstractValueModel, AbstractValueModelWrapper, BufferedCollectionValueModel, BufferedValueModel, DeepCopyBufferedCollectionValueModel, DefaultFormModel.ValidatingFormValueModel, FormModelMediatingValueModel, GrowableIndexAdapter, ListSelectionValueModelAdapter, MapKeyAdapter, MessageFormatValueModel, MethodInvokingDerivedValueModel, RefreshableValueHolder, TypeConverter, ValueHolder

public interface ValueModel

Describes models with a generic access to a single value that allow to observe value changes. The value can be accessed using the #getValue()/#setValue(Object)/ #setValueSilently(Object, PropertyChangeListener) methods. Observers can register instances of PropertyChangeListener to be notified if the value changes.

The listeners registered with this ValueModel using #addValueChangeListener will be invoked only with PropertyChangeEvents that have the name set to "value".

AbstractValueModel minimizes the effort required to implement this interface. It uses the PropertyChangeSupport to fire PropertyChangeEvents, and it adds PropertyChangeListeners for the specific property name "value". This ensures that the constraint mentioned above is met.

Author:

Karsten Lentzsch, Keith Donald, Oliver Hutchison

See Also:

AbstractValueModel

Field Summary

static String

VALUE_PROPERTY The name of the bound property value.

Method Summary

void	addValueChangeListener(PropertyChangeListener listener) Registers the given PropertyChangeListener with this ValueModel.
Object	getValue() Returns this model's value.
void	removeValueChangeListener(PropertyChangeListener listener) Deregisters the given PropertyChangeListener from this ValueModel.
void	setValue(Object newValue) Sets a new value and if the value has changed notifies any registered value change listeners.
void	setValueSilently(Object newValue, PropertyChangeListener listenerToSkip) Sets a new value and if the value has changed notifies all registered value change listeners except for the specified listener to skip.

Field Detail

VALUE_PROPERTY

static final String VALUE_PROPERTY

The name of the bound property value.

See Also:

Constant Field Values

Method Detail

getValue

Object getValue()

Returns this model's value. In case of a write-only value, implementers may choose to either reject this operation or or return null or any other appropriate value.

Returns:

this model's value

setValue

void setValue(Object newValue)

Sets a new value and if the value has changed notifies any registered value change listeners.

Parameters:

newValue - the value to be set

setValueSilently

void setValueSilently(Object newValue,
                      PropertyChangeListener listenerToSkip)

Sets a new value and if the value has changed notifies all registered value change listeners except for the specified listener to skip.

Parameters:

newValue - the value to be set

listenerToSkip - the PropertyChangeListener that should not be notified of this change (may be null).

addValueChangeListener

void addValueChangeListener(PropertyChangeListener listener)

Registers the given PropertyChangeListener with this ValueModel. The listener will be notified if the value has changed. The PropertyChangeEvents delivered to the listener must have the name set to "value". The latter ensures that all ValueModel implementers behave like the AbstractValueModel subclasses.

To comply with the above specification implementers can use the PropertyChangeSupport's #addPropertyChangeListener method that accepts a property name, so that listeners will be invoked only if that specific property has changed.

Parameters:

listener - the listener to be added

See Also:

AbstractValueModel.addValueChangeListener(PropertyChangeListener)

removeValueChangeListener

void removeValueChangeListener(PropertyChangeListener listener)

Deregisters the given PropertyChangeListener from this ValueModel.

Parameters:

listener - the listener to be removed