Package org.apache.commons.collections4.bag

This package contains implementations of the Bag and SortedBag interfaces. A bag stores an object and a count of the number of occurrences of the object.

The following implementations are provided in the package:

• HashBag - implementation that uses a HashMap to store the data
• TreeBag - implementation that uses a TreeMap to store the data

The following decorators are provided in the package:

• Synchronized - synchronizes method access for multi-threaded environments
• Unmodifiable - ensures the bag cannot be altered
• Predicated - ensures that only elements that are valid according to a predicate can be added
• Transformed - transforms each element added to the bag
• Collection - ensures compliance with the java.util.Collection contract

Class Summary

Class	Description
AbstractBagDecorator<E>	Decorates another Bag to provide additional behaviour.
AbstractMapBag<E>	Abstract implementation of the Bag interface to simplify the creation of subclass implementations.
AbstractMapBag.MutableInteger	Mutable integer class for storing the data.
AbstractSortedBagDecorator<E>	Decorates another SortedBag to provide additional behaviour.
CollectionBag<E>	Decorates another Bag to comply with the Collection contract.
CollectionSortedBag<E>	Decorates another SortedBag to comply with the Collection contract.
HashBag<E>	Implements Bag, using a HashMap to provide the data storage.
PredicatedBag<E>	Decorates another Bag to validate that additions match a specified predicate.
PredicatedSortedBag<E>	Decorates another SortedBag to validate that additions match a specified predicate.
SynchronizedBag<E>	Decorates another Bag to synchronize its behaviour for a multi-threaded environment.
SynchronizedSortedBag<E>	Decorates another SortedBag to synchronize its behaviour for a multi-threaded environment.
TransformedBag<E>	Decorates another Bag to transform objects that are added.
TransformedSortedBag<E>	Decorates another SortedBag to transform objects that are added.
TreeBag<E>	Implements SortedBag, using a TreeMap to provide the data storage.
UnmodifiableBag<E>	Decorates another Bag to ensure it can't be altered.
UnmodifiableSortedBag<E>	Decorates another SortedBag to ensure it can't be altered.