org.apache.commons.events.observable
Class ObservableSortedBag

java.lang.Object
  org.apache.commons.collections.collection.AbstractCollectionDecorator
      org.apache.commons.events.observable.ObservableCollection
          org.apache.commons.events.observable.ObservableBag
              org.apache.commons.events.observable.ObservableSortedBag

All Implemented Interfaces:

Iterable, Collection, org.apache.commons.collections.Bag, org.apache.commons.collections.SortedBag

public class ObservableSortedBag
extends ObservableBag
implements org.apache.commons.collections.SortedBag

Decorates a SortedBag implementation to observe modifications.

Each modifying method call made on this SortedBag is forwarded to a ModificationHandler. The handler manages the event, notifying listeners and optionally vetoing changes. The default handler is StandardModificationHandler. See this class for details of configuration available.

Since:

Commons Events 1.0

Version:

$Revision: 155443 $ $Date: 2005-02-26 13:19:51 +0000 (Sat, 26 Feb 2005) $

Author:

Stephen Colebourne

Nested Class Summary

Nested classes/interfaces inherited from class org.apache.commons.events.observable.ObservableCollection

ObservableCollection.ObservableIterator

Field Summary

Fields inherited from class org.apache.commons.events.observable.ObservableCollection

handler

Fields inherited from class org.apache.commons.collections.collection.AbstractCollectionDecorator

collection

Constructor Summary

protected

ObservableSortedBag(org.apache.commons.collections.SortedBag bag, Object listener) Constructor that wraps (not copies) and takes a handler.

Method Summary

Comparator	comparator()
static ObservableSortedBag	decorate(org.apache.commons.collections.SortedBag bag) Factory method to create an observable bag.
static ObservableSortedBag	decorate(org.apache.commons.collections.SortedBag bag, Object listener) Factory method to create an observable bag using a listener or a handler.
Object	first()
Object	last()

Methods inherited from class org.apache.commons.events.observable.ObservableBag

add, add, decorate, decorate, getCount, remove, uniqueSet

Methods inherited from class org.apache.commons.events.observable.ObservableCollection

addAll, clear, createHandler, decorate, decorate, getHandler, iterator, registerFactory, remove, removeAll, retainAll

Methods inherited from class org.apache.commons.collections.collection.AbstractCollectionDecorator

contains, containsAll, equals, getCollection, hashCode, isEmpty, size, toArray, toArray, toString

Methods inherited from class java.lang.Object

clone, finalize, getClass, notify, notifyAll, wait, wait, wait

Methods inherited from interface org.apache.commons.collections.Bag

add, add, containsAll, getCount, iterator, remove, remove, removeAll, retainAll, size, uniqueSet

Methods inherited from interface java.util.Collection

addAll, clear, contains, equals, hashCode, isEmpty, toArray, toArray

Constructor Detail

ObservableSortedBag

protected ObservableSortedBag(org.apache.commons.collections.SortedBag bag,
                              Object listener)

Constructor that wraps (not copies) and takes a handler.

The handler implementation is determined by the listener parameter via the registered factories. The listener may be a manually configured ModificationHandler instance.

Parameters:

bag - the bag to decorate, must not be null

listener - the listener, may be null

Throws:

IllegalArgumentException - if the bag is null

Method Detail

decorate

public static ObservableSortedBag decorate(org.apache.commons.collections.SortedBag bag)

Factory method to create an observable bag.

A StandardModificationHandler will be created. This can be accessed by ObservableCollection.getHandler() to add listeners.

Parameters:

bag - the bag to decorate, must not be null

Returns:

the observed bag

Throws:

IllegalArgumentException - if the collection is null

decorate

public static ObservableSortedBag decorate(org.apache.commons.collections.SortedBag bag,
                                           Object listener)

Factory method to create an observable bag using a listener or a handler.

A lot of functionality is available through this method. If you don't need the extra functionality, simply implement the StandardModificationListener interface and pass it in as the second parameter.

Internally, an ObservableSortedBag relies on a ModificationHandler. The handler receives all the events and processes them, typically by calling listeners. Different handler implementations can be plugged in to provide a flexible event system.

The handler implementation is determined by the listener parameter via the registered factories. The listener may be a manually configured ModificationHandler instance.

The listener is defined as an Object for maximum flexibility. It does not have to be a listener in the classic JavaBean sense. It is entirely up to the factory and handler as to how the parameter is interpretted. An IllegalArgumentException is thrown if no suitable handler can be found for this listener.

A null listener will create a StandardModificationHandler.

Parameters:

bag - the bag to decorate, must not be null

listener - bag listener, may be null

Returns:

the observed bag

Throws:

IllegalArgumentException - if the bag is null

IllegalArgumentException - if there is no valid handler for the listener

comparator

public Comparator comparator()

Specified by:

comparator in interface org.apache.commons.collections.SortedBag

first

public Object first()

Specified by:

first in interface org.apache.commons.collections.SortedBag

last

public Object last()

Specified by:

last in interface org.apache.commons.collections.SortedBag