Package org.apache.wicket.util.watch

Class ModificationWatcher

java.lang.Object

org.apache.wicket.util.watch.ModificationWatcher

All Implemented Interfaces:

IModificationWatcher

public class ModificationWatcher
extends Object
implements IModificationWatcher

Monitors one or more IModifiable objects, calling a IChangeListener when a given object's modification time changes.

Since:

1.2.6

Author:

Jonathan Locke

Nested Class Summary

Nested Classes

Modifier and Type	Class	Description
protected static class	ModificationWatcher.Entry	Container class for holding modifiable entries to watch.

Constructor Summary

Constructors

Constructor	Description
ModificationWatcher()	Default constructor for two-phase construction.
ModificationWatcher(Duration pollFrequency)	Constructor that accepts a Duration argument representing the poll frequency.

Method Summary

Modifier and Type	Method	Description
boolean	add(IModifiable modifiable, IChangeListener<IModifiable> listener)	Adds an IModifiable object and an IChangeListener object to call when the modifiable object is modified.
protected void	checkModified()	Checks which IModifiables were modified and notifies their listeners
void	destroy()	Stops this ModificationWatcher.
Set<IModifiable>	getEntries()	Retrieves a key set of all IModifiable objects currently being monitored.
IModifiable	remove(IModifiable modifiable)	Removes all entries associated with an IModifiable object.
void	start(Duration pollFrequency)	Starts watching at a given Duration polling rate.

Methods inherited from class java.lang.Object

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

Constructor Detail

ModificationWatcher

public ModificationWatcher()

Default constructor for two-phase construction.

ModificationWatcher

public ModificationWatcher(Duration pollFrequency)

Constructor that accepts a Duration argument representing the poll frequency.

Parameters:

pollFrequency - how often to check on IModifiables

Method Detail

add

public final boolean add(IModifiable modifiable,
                         IChangeListener<IModifiable> listener)

Description copied from interface: IModificationWatcher

Adds an IModifiable object and an IChangeListener object to call when the modifiable object is modified.

Specified by:

add in interface IModificationWatcher

Parameters:

modifiable - an IModifiable object to monitor

listener - an IChangeListener to call if the IModifiable object is modified

Returns:

true if the set did not already contain the specified element

remove

public IModifiable remove(IModifiable modifiable)

Description copied from interface: IModificationWatcher

Removes all entries associated with an IModifiable object.

Specified by:

remove in interface IModificationWatcher

Parameters:

modifiable - an IModifiable object

Returns:

the IModifiable object that was removed, else null

start

public void start(Duration pollFrequency)

Description copied from interface: IModificationWatcher

Starts watching at a given Duration polling rate.

Specified by:

start in interface IModificationWatcher

Parameters:

pollFrequency - the polling rate Duration

checkModified

protected void checkModified()

Checks which IModifiables were modified and notifies their listeners

destroy

public void destroy()

Description copied from interface: IModificationWatcher

Stops this ModificationWatcher.

Specified by:

destroy in interface IModificationWatcher

getEntries

public final Set<IModifiable> getEntries()

Description copied from interface: IModificationWatcher

Retrieves a key set of all IModifiable objects currently being monitored.

Specified by:

getEntries in interface IModificationWatcher

Returns:

a Set of all IModifiable entries currently maintained