Package org.apache.commons.collections.set

Class PredicatedSet

  • All Implemented Interfaces:
    Serializable, Iterable, Collection, Set
    Direct Known Subclasses:
    PredicatedSortedSet
    public class PredicatedSet
extends PredicatedCollection
implements Set
    Decorates another Set to validate that all additions match a specified predicate.

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

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

    Set set = PredicatedSet.decorate(new HashSet(), 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:
    Serialized Form

    • Constructor Detail

      • PredicatedSet

        protected PredicatedSet​(Set set,
                        Predicate predicate)
        Constructor that wraps (not copies).

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

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

    • Method Detail

      • decorate

        public static Set decorate​(Set set,
                           Predicate predicate)
        Factory method to create a predicated (validating) set.

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

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

      • getSet

        protected Set getSet()
        Gets the set being decorated.
        Returns:
        the decorated set