Module org.tquadrat.foundation.util

Package org.tquadrat.foundation.util

Interface LazyList<E>

Type Parameters:

E - The type of elements in this list.

All Superinterfaces:

Collection<E>, Iterable<E>, List<E>, SequencedCollection<E>

All Known Implementing Classes:

LazyListImpl

@ClassVersion(sourceVersion="$Id: LazyList.java 1032 2022-04-10 17:27:44Z tquadrat $")
@API(status=STABLE,
     since="0.0.5")
public sealed interface LazyList<E>
extends List<E>
permits LazyListImpl<E>

The interface for a List that will be initialised only when required.

Note:

• There is no implementation of a map() method in this interface because it is assumed that this would be confusing: such a map() method would operate on the whole list that is wrapped by this value, and not on an entry as one would expect. Refer to .

Author:

Thomas Thrien (thomas.thrien@tquadrat.org)

Version:

$Id: LazyList.java 1032 2022-04-10 17:27:44Z tquadrat $

Since:

0.0.5

See Also:

• Lazy

UML Diagram

⁠

UML Diagram for "org.tquadrat.foundation.util.LazyList"

⁠

Method Summary

Modifier and Type	Method	Description
void	ifPresent(Consumer<? super List<E>> consumer)	If this LazyList instance has been initialised already, the provided Consumer will be executed; otherwise nothing happens.
void	init()	Forces the initialisation of this LazyList instance.
boolean	isPresent()	Checks whether this LazyList instance has been initialised already.
static <E> LazyList<E>	of(List<E> value)	Creates a new LazyList instance that is already initialised.
void	sort(Comparator<? super E> c)
static <E> LazyList<E>	use(boolean doPopulate, Supplier<? extends List<E>> supplier)	Creates a new LazyList instance that uses the given supplier to initialise.
static <E> LazyList<E>	use(Supplier<? extends List<E>> supplier)	Creates a new LazyList instance that uses the given supplier to create the internal map, but that supplier does not provide values on initialisation.

Methods inherited from interface java.util.Collection

parallelStream, removeIf, stream, toArray

Methods inherited from interface java.lang.Iterable

forEach

Methods inherited from interface java.util.List

add, add, addAll, addAll, addFirst, addLast, clear, contains, containsAll, equals, get, getFirst, getLast, hashCode, indexOf, isEmpty, iterator, lastIndexOf, listIterator, listIterator, remove, remove, removeAll, removeFirst, removeLast, replaceAll, retainAll, reversed, set, size, spliterator, subList, toArray, toArray

Method Details

ifPresent

void ifPresent(Consumer<? super List<E>> consumer)

If this LazyList instance has been initialised already, the provided Consumer will be executed; otherwise nothing happens.

Parameters:

consumer - The consumer.

init

void init()

Forces the initialisation of this LazyList instance.

isPresent

boolean isPresent()

Checks whether this LazyList instance has been initialised already.

Returns:

true if the instance was initialised, false otherwise.

of

@API(status=STABLE,
     since="0.0.5")
static <E> LazyList<E> of(List<E> value)

Creates a new LazyList instance that is already initialised.

Type Parameters:

E - The type of elements in this list.

Parameters:

value - The value.

Returns:

The new instance.

sort

void sort(Comparator<? super E> c)

Specified by:

sort in interface List<E>

use

@API(status=STABLE,
     since="0.0.5")
static <E> LazyList<E> use(Supplier<? extends List<E>> supplier)

Creates a new LazyList instance that uses the given supplier to create the internal map, but that supplier does not provide values on initialisation.

Type Parameters:

E - The type of elements in this list.

Parameters:

supplier - The supplier that initialises for the new instance of LazyList when needed.

Returns:

The new instance.

use

@API(status=STABLE,
     since="0.0.5")
static <E> LazyList<E> use(boolean doPopulate,
 Supplier<? extends List<E>> supplier)

Creates a new LazyList instance that uses the given supplier to initialise.

Type Parameters:

E - The type of elements in this list.

Parameters:

doPopulate - true if the provided supplier will put entries to the list on initialisation, false if it will create an empty list.

supplier - The supplier that initialises for the new instance of LazyList when needed.

Returns:

The new instance.