Package org.apache.commons.collections4.set

Class TransformedSet<E>

  • Type Parameters:
    E - the type of the elements in this set
    All Implemented Interfaces:
    Serializable, Iterable<E>, Collection<E>, Set<E>
    Direct Known Subclasses:
    TransformedSortedSet
    public class TransformedSet<E>
extends TransformedCollection<E>
implements Set<E>
    Decorates another Set to transform objects that are added.

    The add methods are affected by this class. Thus objects must be removed or searched for using their transformed form. For example, if the transformation converts Strings to Integers, you must use the Integer form to remove objects.

    This class is Serializable from Commons Collections 3.1.

    Since:
    3.0
    See Also:
    Serialized Form

    • Constructor Detail

      • TransformedSet

        protected TransformedSet​(Set<E> set,
                         Transformer<? super E,​? extends E> transformer)
        Constructor that wraps (not copies).

        If there are any elements already in the set being decorated, they are NOT transformed.

        Parameters:
        set - the set to decorate, must not be null
        transformer - the transformer to use for conversion, must not be null
        Throws:
        NullPointerException - if set or transformer is null

    • Method Detail

      • transformingSet

        public static <E> TransformedSet<E> transformingSet​(Set<E> set,
                                                    Transformer<? super E,​? extends E> transformer)
        Factory method to create a transforming set.

        If there are any elements already in the set being decorated, they are NOT transformed. Contrast this with transformedSet(Set, Transformer).

        Type Parameters:
        E - the element type
        Parameters:
        set - the set to decorate, must not be null
        transformer - the transformer to use for conversion, must not be null
        Returns:
        a new transformed set
        Throws:
        NullPointerException - if set or transformer is null
        Since:
        4.0

      • transformedSet

        public static <E> Set<E> transformedSet​(Set<E> set,
                                        Transformer<? super E,​? extends E> transformer)
        Factory method to create a transforming set that will transform existing contents of the specified set.

        If there are any elements already in the set being decorated, they will be transformed by this method. Contrast this with transformingSet(Set, Transformer).

        Type Parameters:
        E - the element type
        Parameters:
        set - the set to decorate, must not be null
        transformer - the transformer to use for conversion, must not be null
        Returns:
        a new transformed set
        Throws:
        NullPointerException - if set or transformer is null
        Since:
        4.0