Package org.apache.commons.collections.bag

Class TreeBag

java.lang.Object
org.apache.commons.collections.bag.AbstractMapBag
org.apache.commons.collections.bag.TreeBag
All Implemented Interfaces:
Serializable, Iterable, Collection, Bag, SortedBag
public class TreeBag extends AbstractMapBag implements SortedBag, Serializable
Implements SortedBag, using a TreeMap to provide the data storage. This is the standard implementation of a sorted bag.

Order will be maintained among the bag members and can be viewed through the iterator.

A Bag stores each object in the collection together with a count of occurrences. Extra methods on the interface allow multiple copies of an object to be added or removed at once. It is important to read the interface javadoc carefully as several methods violate the Collection interface specification.

Since:
Commons Collections 3.0 (previously in main package v2.0)
Version:
$Revision: 646777 $ $Date: 2008-04-10 14:33:15 +0200 (Thu, 10 Apr 2008) $
Author:
Chuck Burdick, Stephen Colebourne
See Also:

  • Constructor Details

    • TreeBag

      public TreeBag()
      Constructs an empty TreeBag.

    • TreeBag

      public TreeBag(Comparator comparator)
      Constructs an empty bag that maintains order on its unique representative members according to the given Comparator.
      Parameters:
      comparator - the comparator to use

    • TreeBag

      public TreeBag(Collection coll)
      Constructs a TreeBag containing all the members of the specified collection.
      Parameters:
      coll - the collection to copy into the bag

  • Method Details

    • first

      public Object first()
      Description copied from interface: SortedBag
      Returns the first (lowest) member.
      Specified by:
      first in interface SortedBag
      Returns:
      the first element in the sorted bag

    • last

      public Object last()
      Description copied from interface: SortedBag
      Returns the last (highest) member.
      Specified by:
      last in interface SortedBag
      Returns:
      the last element in the sorted bag

    • comparator

      public Comparator comparator()
      Description copied from interface: SortedBag
      Returns the comparator associated with this sorted set, or null if it uses its elements' natural ordering.
      Specified by:
      comparator in interface SortedBag
      Returns:
      the comparator in use, or null if natural ordering