Package org.eclipse.core.databinding.observable.value

Class AbstractVetoableValue<T>

java.lang.Object

org.eclipse.core.databinding.observable.AbstractObservable

org.eclipse.core.databinding.observable.value.AbstractObservableValue<T>

org.eclipse.core.databinding.observable.value.AbstractVetoableValue<T>

Type Parameters:

T - the type of value being observed

All Implemented Interfaces:

IObservable, IObservableValue<T>, IVetoableValue<T>

public abstract class AbstractVetoableValue<T>
extends AbstractObservableValue<T>
implements IVetoableValue<T>

This class is thread safe. All state accessing methods must be invoked from the current realm. Methods for adding and removing listeners may be invoked from any thread.

Since:

1.0

Constructor Summary

Constructors

Constructor	Description
AbstractVetoableValue()	Creates a new vetoable value.
AbstractVetoableValue(Realm realm)

Method Summary

Modifier and Type	Method	Description
protected void	addListener(Object listenerType, IObservablesListener listener)
void	addValueChangingListener(IValueChangingListener<T> listener)
protected Object	clone()
protected abstract void	doSetApprovedValue(T value)	Sets the value.
protected void	doSetValue(T value)	Template method for setting the value of the observable.
protected void	fireEvent(ObservableEvent event)
protected boolean	fireValueChanging(ValueDiff<T> diff)	Notifies listeners about a pending change, and returns true if no listener vetoed the change.
protected void	firstListenerAdded()
Realm	getRealm()
protected boolean	hasListeners()
protected void	lastListenerRemoved()
protected void	removeListener(Object listenerType, IObservablesListener listener)
void	removeValueChangingListener(IValueChangingListener<T> listener)

Methods inherited from class org.eclipse.core.databinding.observable.value.AbstractObservableValue

addValueChangeListener, doGetValue, fireChange, fireValueChange, getValue, isStale, removeValueChangeListener, setValue

Methods inherited from class org.eclipse.core.databinding.observable.AbstractObservable

addChangeListener, addDisposeListener, addStaleListener, checkRealm, dispose, fireStale, isDisposed, removeChangeListener, removeDisposeListener, removeStaleListener

Methods inherited from class java.lang.Object

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

Methods inherited from interface org.eclipse.core.databinding.observable.IObservable

addChangeListener, addDisposeListener, addStaleListener, dispose, getRealm, isDisposed, isStale, removeChangeListener, removeDisposeListener, removeStaleListener

Methods inherited from interface org.eclipse.core.databinding.observable.value.IObservableValue

addValueChangeListener, getValue, getValueType, removeValueChangeListener, setValue

Constructor Detail

AbstractVetoableValue

public AbstractVetoableValue()

Creates a new vetoable value.

AbstractVetoableValue

public AbstractVetoableValue(Realm realm)

Parameters:

realm - the realm

Method Detail

doSetValue

protected final void doSetValue(T value)

Description copied from class: AbstractObservableValue

Template method for setting the value of the observable. By default the method throws an UnsupportedOperationException.

Overrides:

doSetValue in class AbstractObservableValue<T>

Parameters:

value - the value to set

doSetApprovedValue

protected abstract void doSetApprovedValue(T value)

Sets the value. Invoked after performing veto checks. Should not fire change events.

Parameters:

value - the approved value to set

addValueChangingListener

public void addValueChangingListener(IValueChangingListener<T> listener)

Specified by:

addValueChangingListener in interface IVetoableValue<T>

Parameters:

listener - the listener to add; not null

removeValueChangingListener

public void removeValueChangingListener(IValueChangingListener<T> listener)

Specified by:

removeValueChangingListener in interface IVetoableValue<T>

Parameters:

listener - the listener to remove; not null

fireValueChanging

protected boolean fireValueChanging(ValueDiff<T> diff)

Notifies listeners about a pending change, and returns true if no listener vetoed the change.

Parameters:

diff - the pending change

Returns:

false if the change was vetoed, true otherwise

addListener

protected void addListener(Object listenerType,
                           IObservablesListener listener)

Parameters:

listenerType - arbitrary object to identify a type of the listener

listener - the listener to add; not null

removeListener

protected void removeListener(Object listenerType,
                              IObservablesListener listener)

Parameters:

listenerType - arbitrary object to identify a type of the listener

listener - the listener to remove; not null

hasListeners

protected boolean hasListeners()

fireEvent

protected void fireEvent(ObservableEvent event)

firstListenerAdded

protected void firstListenerAdded()

lastListenerRemoved

protected void lastListenerRemoved()

getRealm

public Realm getRealm()

Returns:

Returns the realm.

clone

protected Object clone()
                throws CloneNotSupportedException

Overrides:

clone in class Object

Throws:

CloneNotSupportedException