Package org.apache.commons.collections.bag

Class PredicatedSortedBag

java.lang.Object
org.apache.commons.collections.collection.AbstractCollectionDecorator
org.apache.commons.collections.collection.AbstractSerializableCollectionDecorator
org.apache.commons.collections.collection.PredicatedCollection
org.apache.commons.collections.bag.PredicatedBag
org.apache.commons.collections.bag.PredicatedSortedBag
All Implemented Interfaces:
Serializable, Iterable, Collection, Bag, SortedBag
public class PredicatedSortedBag extends PredicatedBag implements SortedBag
Decorates another SortedBag to validate that additions match a specified predicate.

This bag exists to provide validation for the decorated bag. It is normally created to decorate an empty bag. If an object cannot be added to the bag, an IllegalArgumentException is thrown.

One usage would be to ensure that no null entries are added to the bag. 

SortedBag bag = PredicatedSortedBag.decorate(new TreeBag(), NotNullPredicate.INSTANCE);

This class is Serializable from Commons Collections 3.1.

Since:
Commons Collections 3.0
Version:
$Revision: 646777 $ $Date: 2008-04-10 14:33:15 +0200 (Thu, 10 Apr 2008) $
Author:
Stephen Colebourne, Paul Jack
See Also:

  • Constructor Details

    • PredicatedSortedBag

      protected PredicatedSortedBag(SortedBag bag, Predicate predicate)
      Constructor that wraps (not copies).

      If there are any elements already in the bag being decorated, they are validated.

      Parameters:
      bag - the bag to decorate, must not be null
      predicate - the predicate to use for validation, must not be null
      Throws:
      IllegalArgumentException - if bag or predicate is null
      IllegalArgumentException - if the bag contains invalid elements

  • Method Details

    • decorate

      public static SortedBag decorate(SortedBag bag, Predicate predicate)
      Factory method to create a predicated (validating) bag.

      If there are any elements already in the bag being decorated, they are validated.

      Parameters:
      bag - the bag to decorate, must not be null
      predicate - the predicate to use for validation, must not be null
      Returns:
      a new predicated SortedBag
      Throws:
      IllegalArgumentException - if bag or predicate is null
      IllegalArgumentException - if the bag contains invalid elements

    • getSortedBag

      protected SortedBag getSortedBag()
      Gets the decorated sorted bag.
      Returns:
      the decorated bag

    • 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