Package org.apache.commons.collections4.multiset

This package contains implementations of the MultiSet interface. A multiset stores an object and a count of the number of occurrences of the object.

The following implementations are provided in the package:

• HashMultiSet - implementation that uses a HashMap to store the data

The following decorators are provided in the package:

• Predicated - ensures that only elements that are valid according to a predicate can be added
• Synchronized - synchronizes method access for multi-threaded environments
• Unmodifiable - ensures the multiset cannot be altered

Class Summary

Class	Description
AbstractMapMultiSet<E>	Abstract implementation of the MultiSet interface to simplify the creation of subclass implementations.
AbstractMultiSet<E>	Abstract implementation of the MultiSet interface to simplify the creation of subclass implementations.
AbstractMultiSetDecorator<E>	Decorates another MultSet to provide additional behaviour.
HashMultiSet<E>	Implements MultiSet, using a HashMap to provide the data storage.
PredicatedMultiSet<E>	Decorates another MultiSet to validate that additions match a specified predicate.
SynchronizedMultiSet<E>	Decorates another MultiSet to synchronize its behaviour for a multi-threaded environment.
UnmodifiableMultiSet<E>	Decorates another MultiSet to ensure it can't be altered.