com.bluegosling.collections

Class TransformingCollection.Bidi<I,O>

java.lang.Object

com.bluegosling.collections.TransformingIterable<I,O>

com.bluegosling.collections.TransformingCollection<I,O>

com.bluegosling.collections.TransformingCollection.Bidi<I,O>

Type Parameters:

I - the "input" type; the type of the wrapped collection

O - the "output" type; the type of elements in this collection

All Implemented Interfaces:

Iterable<O>, Collection<O>

Direct Known Subclasses:

TransformingSet.Bidi

Enclosing class:

TransformingCollection<I,O>

public static class TransformingCollection.Bidi<I,O>
extends TransformingCollection<I,O>

A transforming collection that can transform values in both directions. Since this collection can transform values in the other direction (output type -> input type), all operations are supported, including add(Object) and addAll(Collection).

Several methods are overridden to use the reverse function before delegating to the underlying list. Since some of these interface methods actually accept any type of object (instead of requiring the list's element type), this implementation could result in ClassCastExceptions if objects with incorrect types are passed to them. These methods are contains(Object), containsAll(Collection), remove(Object), removeAll(Collection), and retainAll(Collection).

Nested Class Summary

Nested classes/interfaces inherited from class com.bluegosling.collections.TransformingCollection

TransformingCollection.Bidi<I,O>, TransformingCollection.ReadOnly<I,O>

Constructor Summary

Constructors

Constructor and Description
Bidi(Collection<I> collection, Function<? super I,? extends O> function1, Function<? super O,? extends I> function2) Constructs a new bidirectional transforming collection.

Method Summary

Modifier and Type	Method and Description
boolean	add(O e)
boolean	addAll(Collection<? extends O> c)
boolean	contains(Object o)
boolean	containsAll(Collection<?> c)
protected Function<? super O,? extends I>	inverseFunction() Gets the function used to transform elements from the "output" domain to the "input" domain.
boolean	remove(Object o)
boolean	removeAll(Collection<?> c)
boolean	retainAll(Collection<?> c)
protected I	unapply(Object input) Transforms "output" elements into "input" elements.
protected Collection<I>	unapplyAll(Collection<?> c) Transforms a collection of "output" elements into "input" elements.

Methods inherited from class com.bluegosling.collections.TransformingCollection

clear, internal, isEmpty, size, toArray, toArray, toString

Methods inherited from class com.bluegosling.collections.TransformingIterable

apply, function, iterator

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, wait, wait, wait

Methods inherited from interface java.util.Collection

equals, hashCode, iterator, parallelStream, removeIf, spliterator, stream

Methods inherited from interface java.lang.Iterable

forEach

Constructor Detail

Bidi

public Bidi(Collection<I> collection,
            Function<? super I,? extends O> function1,
            Function<? super O,? extends I> function2)

Constructs a new bidirectional transforming collection. The two provided functions must be inverses of one another. In other words, for any object i in the input domain, i must equal function2.apply(function1.apply(i)). Similarly, for any object o in the output domain, o must equal function1.apply(function2.apply(o)).

Parameters:

collection - the wrapped collection

function1 - transforms elements; "input" -> "output"

function2 - the inverse of function1; "output" -> "input"

Method Detail

inverseFunction

protected Function<? super O,? extends I> inverseFunction()

Gets the function used to transform elements from the "output" domain to the "input" domain. This is the inverse of TransformingIterable.function().

Returns:

the inverse function

unapply

protected I unapply(Object input)

Transforms "output" elements into "input" elements. This is the opposite direction as TransformingIterable.apply(Object).

Parameters:

input - the object to transform, which should be of type O

Returns:

the transformed result

unapplyAll

protected Collection<I> unapplyAll(Collection<?> c)

Transforms a collection of "output" elements into "input" elements.

Parameters:

c - the collection to transform, whose elements should be of type O

Returns:

the transformed results

add

public boolean add(O e)

Specified by:

add in interface Collection<O>

Overrides:

add in class TransformingCollection<I,O>

remove

public boolean remove(Object o)

Specified by:

remove in interface Collection<O>

Overrides:

remove in class TransformingCollection<I,O>

contains

public boolean contains(Object o)

Specified by:

contains in interface Collection<O>

Overrides:

contains in class TransformingCollection<I,O>

containsAll

public boolean containsAll(Collection<?> c)

Specified by:

containsAll in interface Collection<O>

Overrides:

containsAll in class TransformingCollection<I,O>

removeAll

public boolean removeAll(Collection<?> c)

Specified by:

removeAll in interface Collection<O>

Overrides:

removeAll in class TransformingCollection<I,O>

retainAll

public boolean retainAll(Collection<?> c)

Specified by:

retainAll in interface Collection<O>

Overrides:

retainAll in class TransformingCollection<I,O>

addAll

public boolean addAll(Collection<? extends O> c)

Specified by:

addAll in interface Collection<O>

Overrides:

addAll in class TransformingCollection<I,O>