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