Class WeightedList<E>

java.lang.Object

dev.wyck.util.WeightedList<E>

@NullMarked
@AsOf("2.3.0")
public final class WeightedList<E>
extends Object

A simple weighted random list.

Below FLAT_THRESHOLD total weight it uses a flat lookup array (O(1) draw, memory proportional to total weight); at or above it, a linear scan (O(n) draw, O(n) memory).

Nested Class Summary

Nested Classes

Modifier and Type	Class	Description
static class	WeightedList.Builder<E>
static final record	WeightedList.Weighted<E>	A value paired with its selection weight.

Method Summary

Modifier and Type	Method	Description
static <E> WeightedList.Builder<E>	builder()
boolean	contains(E element)
Optional<E>	getRandom(RandomGenerator random)
E	getRandomOrThrow(RandomGenerator random)
boolean	isEmpty()
static <E> WeightedList<E>	of()
static <E> WeightedList<E>	of(WeightedList.Weighted<E>... items)
static <E> WeightedList<E>	of(E element)
static <E> WeightedList<E>	of(List<WeightedList.Weighted<E>> items)
List<WeightedList.Weighted<E>>	unwrap()

Methods inherited from class Object

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

Method Details

of

public static <E> WeightedList<E> of()

of

public static <E> WeightedList<E> of(E element)

of

@SafeVarargs
public static <E> WeightedList<E> of(WeightedList.Weighted<E>... items)

of

public static <E> WeightedList<E> of(List<WeightedList.Weighted<E>> items)

builder

public static <E> WeightedList.Builder<E> builder()

isEmpty

public boolean isEmpty()

getRandom

public Optional<E> getRandom(RandomGenerator random)

getRandomOrThrow

public E getRandomOrThrow(RandomGenerator random)

unwrap

public List<WeightedList.Weighted<E>> unwrap()

contains

public boolean contains(E element)