public final class DelayedReadValueModel extends AbstractValueModel
Wraps a given subject ValueModel and observes subject value changes and forwards them to listeners of this model after a delay. If the subject value changes, a Swing Timer is used to delay the change notification. A previously started timer - if any - will be stopped before. Reading this model's value returns: a) the subject value if there's no pending update, or b) this model's old value that will be updated after the delay. If a value is set to this model, it immediately updates the subject value.
TODO: Describe how and when listeners get notified about the delayed change.
TODO: Write about the recommended delay time - above the double-click time and somewhere below a second, e.g. 100ms to 200ms.
TODO: Write about a slightly different commit handling. The current implementation defers the commit until the value is stable for the specified delay; it's a DelayUntilStableForXXXmsValueModel. Another feature is to delay for a specified time but ensure that some commits and change notifications happen. The latter is a CoalescingWriteValueModel.
TODO: Summarize the differences between the DelayedReadValueModel, the DelayedWriteValueModel, and the DelayedPropertyChangeHandler.
Timer
,
Serialized FormPROPERTY_VALUE
Constructor and Description |
---|
DelayedReadValueModel(ValueModel subject,
int delay)
Constructs a DelayedReadValueModel for the given subject ValueModel
and the specified Timer delay in milliseconds with coalescing disabled.
|
DelayedReadValueModel(ValueModel subject,
int delay,
boolean coalesce)
Constructs a DelayedReadValueModel for the given subject ValueModel
and the specified Timer delay in milliseconds using the given
coalesce mode.
|
Modifier and Type | Method and Description |
---|---|
int |
getDelay()
Returns the delay, in milliseconds, that is used to defer value change
notifications.
|
Object |
getValue()
Returns the subject's value or in case of a pending commit,
the pending new value.
|
boolean |
isCoalesce()
Returns if this model coalesces all pending changes or not.
|
boolean |
isPending()
Checks and answers whether this model has one or more pending changes.
|
void |
setCoalesce(boolean b)
Sets if this model shall coalesce all pending changes or not.
|
void |
setDelay(int delay)
Sets the delay, in milliseconds, that is used to defer value change
notifications.
|
void |
setValue(Object newValue)
Sets the given new value immediately as the subject's new value.
|
void |
stop()
Stops a running timer.
|
addValueChangeListener, booleanValue, doubleValue, fireValueChange, fireValueChange, fireValueChange, fireValueChange, fireValueChange, fireValueChange, fireValueChange, floatValue, getString, intValue, longValue, paramString, removeValueChangeListener, setValue, setValue, setValue, setValue, setValue, toString, valueString
createPropertyChangeSupport, firePropertyChange
addPropertyChangeListener, addPropertyChangeListener, addVetoableChangeListener, addVetoableChangeListener, fireIndexedPropertyChange, fireIndexedPropertyChange, fireIndexedPropertyChange, fireMultiplePropertiesChanged, firePropertyChange, firePropertyChange, firePropertyChange, firePropertyChange, firePropertyChange, firePropertyChange, firePropertyChange, fireVetoableChange, fireVetoableChange, fireVetoableChange, fireVetoableChange, fireVetoableChange, fireVetoableChange, fireVetoableChange, getPropertyChangeListeners, getPropertyChangeListeners, getVetoableChangeListeners, getVetoableChangeListeners, removePropertyChangeListener, removePropertyChangeListener, removeVetoableChangeListener, removeVetoableChangeListener
public DelayedReadValueModel(ValueModel subject, int delay)
subject
- the underlying (or wrapped) ValueModeldelay
- the milliseconds to wait before a change
shall be committedIllegalArgumentException
- if the delay is negativepublic DelayedReadValueModel(ValueModel subject, int delay, boolean coalesce)
subject
- the underlying (or wrapped) ValueModeldelay
- the milliseconds to wait before a change
shall be committedcoalesce
- true
to coalesce all pending changes,
false
to fire changes with the delay when an update
has been receivedIllegalArgumentException
- if the delay is negativesetCoalesce(boolean)
public Object getValue()
public void setValue(Object newValue)
newValue
- the value to setpublic int getDelay()
setDelay(int)
public void setDelay(int delay)
delay
- the delay, in milliseconds, that is used to defer
value change notificationsgetDelay()
public boolean isCoalesce()
true
if all pending changes will be coalesced,
false
if pending changes are fired with a delay
when an update has been received.setCoalesce(boolean)
public void setCoalesce(boolean b)
false
, a change event will be fired
with this model's delay when an update has been received.
The default value is false
.
Note that this value is not the #coalesce value of this model's internal Swing timer.
b
- true
to coalesce,
false
to fire separate changespublic void stop()
ValueUpdateListener
.public boolean isPending()
true
if there are pending changes, false
if not.Copyright © 2002-2015 JGoodies Software GmbH. All Rights Reserved.