Interface List<T>
- Type Parameters:
T
- Component type of the List
- All Superinterfaces:
Foldable<T>
,Function<Integer,
,T> Function1<Integer,
,T> Iterable<T>
,LinearSeq<T>
,PartialFunction<Integer,
,T> Seq<T>
,Serializable
,Traversable<T>
,Value<T>
List
is an eager sequence of elements. Its immutability makes it suitable for concurrent programming.
A List
is composed of a head
element and a tail
List
.
There are two implementations of the List
interface:
List.Nil
, which represents the emptyList
.List.Cons
, which represents aList
containing one or more elements.
List
is a Stack
in the sense that it stores elements allowing a last-in-first-out (LIFO) retrieval.
Stack API:
peek()
peekOption()
pop()
popOption()
pop2()
pop2Option()
push(Object)
push(Object[])
pushAll(Iterable)
List
:
// factory methods
List.empty() // = List.of() = Nil.instance()
List.of(x) // = new Cons<>(x, Nil.instance())
List.of(Object...) // e.g. List.of(1, 2, 3)
List.ofAll(Iterable) // e.g. List.ofAll(Stream.of(1, 2, 3)) = 1, 2, 3
List.ofAll(<primitive array>) // e.g. List.of(new int[] {1, 2, 3}) = 1, 2, 3
// int sequences
List.range(0, 3) // = 0, 1, 2
List.rangeClosed(0, 3) // = 0, 1, 2, 3
Note: A List
is primarily a Seq
and extends Stack
for technical reasons (so Stack
does not need to wrap List
).
If operating on a List
, please prefer
prepend(Object)
overpush(Object)
prependAll(Iterable)
overpushAll(Iterable)
tail()
overpop()
tailOption()
overpopOption()
List<Integer> s1 = List.of(1);
List<Integer> s2 = List.of(1, 2, 3);
// = List.of(new Integer[] {1, 2, 3});
List<int[]> s3 = List.ofAll(1, 2, 3);
List<List<Integer>> s4 = List.ofAll(List.of(1, 2, 3));
List<Integer> s5 = List.ofAll(1, 2, 3);
List<Integer> s6 = List.ofAll(List.of(1, 2, 3));
// cuckoo's egg
List<Integer[]> s7 = List.<Integer[]> of(new Integer[] {1, 2, 3});
Example: Converting a String to digits
// = List(1, 2, 3)
List.of("123".toCharArray()).map(c -> Character.digit(c, 10))
See Okasaki, Chris: Purely Functional Data Structures (p. 7 ff.). Cambridge, 2003.-
Nested Class Summary
Nested Classes -
Field Summary
Fields -
Method Summary
Modifier and TypeMethodDescriptionAppends an element to this.Appends all given elements to this.asJava()
Creates an immutableList
view on top of thisSeq
, i.e.Creates a mutableList
view on top of thisSeq
, i.e.asJavaMutable
(Consumer<? super List<T>> action) default <R> List
<R> collect
(PartialFunction<? super T, ? extends R> partialFunction) Collects all elements that are in the domain of the givenpartialFunction
by mapping the elements to typeR
.Returns aCollector
which may be used in conjunction withStream.collect(java.util.stream.Collector)
to obtain aList
.Returns the union of all combinations from k = 0 to length().combinations
(int k) Returns the k-combination of this traversable, i.e.crossProduct
(int power) Calculates the n-ary cartesian power (or cross product or simply product) of this.distinct()
Returns a new version of this which contains no duplicates.distinctBy
(Comparator<? super T> comparator) Returns a new version of this which contains no duplicates.distinctBy
(Function<? super T, ? extends U> keyExtractor) Returns a new version of this which contains no duplicates.drop
(int n) Drops the first n elements of this or all elements, if this length < n.dropRight
(int n) Drops the last n elements of this or all elements, if this length < n.dropRightUntil
(Predicate<? super T> predicate) Drops elements until the predicate holds for the current element, starting from the end.dropRightWhile
(Predicate<? super T> predicate) Drops elements while the predicate holds for the current element, starting from the end.Drops elements until the predicate holds for the current element.Drops elements while the predicate holds for the current element.static <T> List
<T> empty()
Returns the single instance of Nil.static <T> List
<T> Returns a List containingn
values supplied by a given Suppliers
.static <T> List
<T> fill
(int n, T element) Returns a List containingn
times the givenelement
Returns a new traversable consisting of all elements which satisfy the given predicate.default <U> List
<U> FlatMaps this Traversable.default T
get
(int index) Returns the element at the specified index.Groups this elements by classifying the elements.grouped
(int size) Groups thisTraversable
into fixed size blocks.default boolean
Checks if this Traversable is known to have a finite size.default int
Returns the index of the first occurrence of the given element after or at some start index or -1 if this does not contain the given element.init()
Dual of Traversable.tail(), returning all elements except the last.Dual of Traversable.tailOption(), returning all elements except the last asOption
.Inserts the given element at the specified index.Inserts the given elements at the specified index.intersperse
(T element) Inserts an element between all elements of this Traversable.default boolean
isAsync()
AList
is computed synchronously.boolean
isEmpty()
Checks if this Traversable is empty.default boolean
isLazy()
AList
is computed eagerly.default boolean
Checks if this Traversable can be repeatedly traversed.default T
last()
Dual of Traversable.head(), returning the last element.default int
lastIndexOf
(T element, int end) Returns the index of the last occurrence of the given element before or at a given end index or -1 if this does not contain the given element.A copy of this sequence with an element prepended until a given target length is reached.int
length()
Computes the number of elements of this Traversable.default <U> List
<U> Maps the elements of thisTraversable
to elements of a new type preserving their order, if any.static <T> List
<T> Narrows a widenedList<? extends T>
toList<T>
by performing a type-safe cast.static <T> List
<T> of
(T element) Returns a singletonList
, i.e.static <T> List
<T> of
(T... elements) Creates a List of the given elements.ofAll
(boolean... elements) Creates a List from boolean values.ofAll
(byte... elements) Creates a List from byte values.ofAll
(char... elements) Creates a List from char values.ofAll
(double... elements) Creates a List from double values.ofAll
(float... elements) Creates a List from float values.ofAll
(int... elements) Creates a List from int values.ofAll
(long... elements) Creates a List from long values.ofAll
(short... elements) Creates a List from short values.static <T> List
<T> Creates a List of the given elements.static <T> List
<T> Creates a List that contains the elements of the givenStream
.Returns thisTraversable
if it is nonempty, otherwise return the alternative.Returns thisTraversable
if it is nonempty, otherwise return the result of evaluating supplier.A copy of this sequence with an element appended until a given target length is reached.Creates a partition of thisTraversable
by splitting this elements in two in distinct traversables according to a predicate.Produces a new list where a slice of elements in this list is replaced by another sequence.default T
peek()
Returns the head element without modifying the List.Performs an action on the head element of thisList
.Returns the head element without modifying the List.Computes all unique permutations.pop()
Removes the head element from this List.pop2()
Removes the head element from this List.Removes the head element from this List.Removes the head element from this List.Prepends an element to this.prependAll
(Iterable<? extends T> elements) Prepends all given elements to this.Pushes a new element on top of this List.Pushes the given elements on top of this List.Pushes the given elements on top of this List.range
(char from, char toExclusive) range
(int from, int toExclusive) Creates a List of int numbers starting fromfrom
, extending totoExclusive - 1
.range
(long from, long toExclusive) Creates a List of long numbers starting fromfrom
, extending totoExclusive - 1
.rangeBy
(char from, char toExclusive, int step) rangeBy
(double from, double toExclusive, double step) rangeBy
(int from, int toExclusive, int step) Creates a List of int numbers starting fromfrom
, extending totoExclusive - 1
, withstep
.rangeBy
(long from, long toExclusive, long step) Creates a List of long numbers starting fromfrom
, extending totoExclusive - 1
, withstep
.rangeClosed
(char from, char toInclusive) rangeClosed
(int from, int toInclusive) Creates a List of int numbers starting fromfrom
, extending totoInclusive
.rangeClosed
(long from, long toInclusive) Creates a List of long numbers starting fromfrom
, extending totoInclusive
.rangeClosedBy
(char from, char toInclusive, int step) rangeClosedBy
(double from, double toInclusive, double step) rangeClosedBy
(int from, int toInclusive, int step) Creates a List of int numbers starting fromfrom
, extending totoInclusive
, withstep
.rangeClosedBy
(long from, long toInclusive, long step) Creates a List of long numbers starting fromfrom
, extending totoInclusive
, withstep
.Returns a new traversable consisting of all elements which do not satisfy the given predicate.Removes the first occurrence of the given element.Removes all occurrences of the given elements.Deprecated.Removes all occurrences of the given element.removeAt
(int index) Removes the element at the specified position in this sequence.removeFirst
(Predicate<T> predicate) Removes the first occurrence that satisfy predicateremoveLast
(Predicate<T> predicate) Removes the last occurrence that satisfy predicateReplaces the first occurrence (if exists) of the given currentElement with newElement.replaceAll
(T currentElement, T newElement) Replaces all occurrences of the given currentElement with newElement.Keeps all occurrences of the given elements from this.reverse()
Reverses the order of elements.rotateLeft
(int n) Circular rotates the elements by the specified distance to the left direction.rotateRight
(int n) Circular rotates the elements by the specified distance to the right direction.Computes a prefix scan of the elements of the collection.default <U> List
<U> scanLeft
(U zero, BiFunction<? super U, ? super T, ? extends U> operation) Produces a collection containing cumulative results of applying the operator going left to right.default <U> List
<U> scanRight
(U zero, BiFunction<? super T, ? super U, ? extends U> operation) Produces a collection containing cumulative results of applying the operator going right to left.shuffle()
Randomize the order of the elements in the current sequence.slice
(int beginIndex, int endIndex) Returns a Seq that is a slice of this.Slides a non-overlapping window of a variable size over thisTraversable
.sliding
(int size) Slides a window of a specificsize
and step size 1 over thisTraversable
by callingTraversable.sliding(int, int)
.sliding
(int size, int step) Slides a window of a specificsize
andstep
size over thisTraversable
.sortBy
(Comparator<? super U> comparator, Function<? super T, ? extends U> mapper) Sorts this elements by comparing the elements in a different domain, using the givenmapper
.default <U extends Comparable<? super U>>
List<T> Sorts this elements by comparing the elements in a different domain, using the givenmapper
.sorted()
Sorts this elements according to their natural order.sorted
(Comparator<? super T> comparator) Sorts this elements according to the providedComparator
.Returns a tuple where the first element is the longest prefix of elements that satisfy the givenpredicate
and the second element is the remainder.splitAt
(int n) Splits a Seq at the specified index.Splits a sequence at the first element which satisfies thePredicate
, e.g.splitAtInclusive
(Predicate<? super T> predicate) Splits a sequence at the first element which satisfies thePredicate
, e.g.default String
Returns the name of this Value type, which is used by toString().subSequence
(int beginIndex) Returns a Seq that is a subsequence of this.subSequence
(int beginIndex, int endIndex) Returns a Seq that is a subsequence of this.static <T> List
<T> Returns a List containingn
values of a given Functionf
over a range of integer values from 0 ton - 1
.tail()
Drops the first element of a non-empty Traversable.Drops the first element of a non-empty Traversable and returns anOption
.take
(int n) Takes the first n elements of this or all elements, if this length < n.takeRight
(int n) Takes the last n elements of this or all elements, if this length < n.takeRightUntil
(Predicate<? super T> predicate) Takes elements until the predicate holds for the current element, starting from the end.takeRightWhile
(Predicate<? super T> predicate) Takes elements while the predicate holds for the current element, starting from the end.Takes elements until the predicate holds for the current element.Takes elements while the predicate holds for the current element.default <U> U
Transforms thisList
.Transposes the rows and columns of aList
matrix.static <T> List
<T> Creates a list from a seed value and a function.static <T,
U> List <U> unfoldLeft
(T seed, Function<? super T, Option<Tuple2<? extends T, ? extends U>>> f) Creates a list from a seed value and a function.static <T,
U> List <U> unfoldRight
(T seed, Function<? super T, Option<Tuple2<? extends U, ? extends T>>> f) Creates a list from a seed value and a function.Unzips this elements by mapping this elements to pairs which are subsequently split into two distinct sets.Unzips this elements by mapping this elements to triples which are subsequently split into three distinct sets.Updates the given element at the specified index using the specified function.Updates the given element at the specified index.Returns a traversable formed from this traversable and another Iterable collection by combining corresponding elements in pairs.Returns a traversable formed from this traversable and another Iterable by combining corresponding elements in pairs.default <U,
R> List <R> zipWith
(Iterable<? extends U> that, BiFunction<? super T, ? super U, ? extends R> mapper) Returns a traversable formed from this traversable and another Iterable collection by mapping elements.Zips this traversable with its indices.default <U> List
<U> zipWithIndex
(BiFunction<? super T, ? super Integer, ? extends U> mapper) Zips this traversable with its indices by applying mapper provided.Methods inherited from interface io.vavr.collection.Foldable
fold, reduce, reduceOption
Methods inherited from interface io.vavr.Function1
andThen, arity, compose, curried, isMemoized, memoized, partial, reversed, tupled
Methods inherited from interface io.vavr.collection.LinearSeq
asPartialFunction, indexOfSlice, indexWhere, isDefinedAt, lastIndexOfSlice, lastIndexWhere, reverseIterator, search, search, segmentLength
Methods inherited from interface io.vavr.collection.Seq
apply, containsSlice, crossProduct, crossProduct, endsWith, foldRight, indexOf, indexOfOption, indexOfOption, indexOfSlice, indexOfSliceOption, indexOfSliceOption, indexWhere, indexWhereOption, indexWhereOption, isSequential, iterator, lastIndexOf, lastIndexOfOption, lastIndexOfOption, lastIndexOfSlice, lastIndexOfSliceOption, lastIndexOfSliceOption, lastIndexWhere, lastIndexWhereOption, lastIndexWhereOption, lift, prefixLength, startsWith, startsWith, withDefault, withDefaultValue
Methods inherited from interface io.vavr.collection.Traversable
arrangeBy, average, containsAll, count, equals, existsUnique, find, findLast, foldLeft, forEachWithIndex, get, hashCode, head, headOption, isDistinct, isOrdered, isSingleValued, iterator, lastOption, max, maxBy, maxBy, min, minBy, minBy, mkCharSeq, mkCharSeq, mkCharSeq, mkString, mkString, mkString, nonEmpty, product, reduceLeft, reduceLeftOption, reduceRight, reduceRightOption, single, singleOption, size, spliterator, sum
Methods inherited from interface io.vavr.Value
collect, collect, contains, corresponds, eq, exists, forAll, forEach, getOrElse, getOrElse, getOrElseThrow, getOrElseTry, getOrNull, out, out, stderr, stdout, toArray, toCharSeq, toCompletableFuture, toEither, toEither, toInvalid, toInvalid, toJavaArray, toJavaArray, toJavaArray, toJavaCollection, toJavaList, toJavaList, toJavaMap, toJavaMap, toJavaMap, toJavaOptional, toJavaParallelStream, toJavaSet, toJavaSet, toJavaStream, toLeft, toLeft, toLinkedMap, toLinkedMap, toLinkedSet, toList, toMap, toMap, toOption, toPriorityQueue, toPriorityQueue, toQueue, toRight, toRight, toSet, toSortedMap, toSortedMap, toSortedMap, toSortedMap, toSortedSet, toSortedSet, toStream, toString, toTree, toTree, toTry, toTry, toValid, toValid, toValidation, toValidation, toVector
-
Field Details
-
serialVersionUID
static final long serialVersionUID- See Also:
-
-
Method Details
-
collector
Returns aCollector
which may be used in conjunction withStream.collect(java.util.stream.Collector)
to obtain aList
.- Type Parameters:
T
- Component type of the List.- Returns:
- A io.vavr.collection.List Collector.
-
empty
Returns the single instance of Nil. Convenience method forNil.instance()
.Note: this method intentionally returns type
List
and notNil
. This comes handy when folding. If you explicitly need typeNil
use List.Nil.instance().- Type Parameters:
T
- Component type of Nil, determined by type inference in the particular context.- Returns:
- The empty list.
-
isAsync
default boolean isAsync()AList
is computed synchronously. -
isEmpty
boolean isEmpty()Description copied from interface:Traversable
Checks if this Traversable is empty. -
isLazy
default boolean isLazy()AList
is computed eagerly. -
narrow
Narrows a widenedList<? extends T>
toList<T>
by performing a type-safe cast. This is eligible because immutable/read-only collections are covariant.- Type Parameters:
T
- Component type of theList
.- Parameters:
list
- AList
.- Returns:
- the given
list
instance as narrowed typeList<T>
.
-
of
Returns a singletonList
, i.e. aList
of one element.- Type Parameters:
T
- The component type- Parameters:
element
- An element.- Returns:
- A new List instance containing the given element
-
of
Creates a List of the given elements.List.of(1, 2, 3, 4) = Nil.instance().prepend(4).prepend(3).prepend(2).prepend(1) = new Cons(1, new Cons(2, new Cons(3, new Cons(4, Nil.instance()))))
- Type Parameters:
T
- Component type of the List.- Parameters:
elements
- Zero or more elements.- Returns:
- A list containing the given elements in the same order.
- Throws:
NullPointerException
- ifelements
is null
-
ofAll
Creates a List of the given elements.The resulting list has the same iteration order as the given iterable of elements if the iteration order of the elements is stable.
- Type Parameters:
T
- Component type of the List.- Parameters:
elements
- An Iterable of elements.- Returns:
- A list containing the given elements in the same order.
- Throws:
NullPointerException
- ifelements
is null
-
ofAll
Creates a List that contains the elements of the givenStream
.- Type Parameters:
T
- Component type of the Stream.- Parameters:
javaStream
- AStream
- Returns:
- A List containing the given elements in the same order.
-
ofAll
Creates a List from boolean values.- Parameters:
elements
- boolean values- Returns:
- A new List of Boolean values
- Throws:
NullPointerException
- if elements is null
-
ofAll
Creates a List from byte values.- Parameters:
elements
- byte values- Returns:
- A new List of Byte values
- Throws:
NullPointerException
- if elements is null
-
ofAll
Creates a List from char values.- Parameters:
elements
- char values- Returns:
- A new List of Character values
- Throws:
NullPointerException
- if elements is null
-
ofAll
Creates a List from double values.- Parameters:
elements
- double values- Returns:
- A new List of Double values
- Throws:
NullPointerException
- if elements is null
-
ofAll
Creates a List from float values.- Parameters:
elements
- a float values- Returns:
- A new List of Float values
- Throws:
NullPointerException
- if elements is null
-
ofAll
Creates a List from int values.- Parameters:
elements
- int values- Returns:
- A new List of Integer values
- Throws:
NullPointerException
- if elements is null
-
ofAll
Creates a List from long values.- Parameters:
elements
- long values- Returns:
- A new List of Long values
- Throws:
NullPointerException
- if elements is null
-
ofAll
Creates a List from short values.- Parameters:
elements
- short values- Returns:
- A new List of Short values
- Throws:
NullPointerException
- if elements is null
-
tabulate
Returns a List containingn
values of a given Functionf
over a range of integer values from 0 ton - 1
.- Type Parameters:
T
- Component type of the List- Parameters:
n
- The number of elements in the Listf
- The Function computing element values- Returns:
- A List consisting of elements
f(0),f(1), ..., f(n - 1)
- Throws:
NullPointerException
- iff
is null
-
fill
Returns a List containingn
values supplied by a given Suppliers
.- Type Parameters:
T
- Component type of the List- Parameters:
n
- The number of elements in the Lists
- The Supplier computing element values- Returns:
- A List of size
n
, where each element contains the result supplied bys
. - Throws:
NullPointerException
- ifs
is null
-
fill
Returns a List containingn
times the givenelement
- Type Parameters:
T
- Component type of the List- Parameters:
n
- The number of elements in the Listelement
- The element- Returns:
- A List of size
n
, where each element is the givenelement
.
-
range
-
rangeBy
-
rangeBy
-
range
Creates a List of int numbers starting fromfrom
, extending totoExclusive - 1
.Examples:
List.range(0, 0) // = List() List.range(2, 0) // = List() List.range(-2, 2) // = List(-2, -1, 0, 1)
- Parameters:
from
- the first numbertoExclusive
- the last number + 1- Returns:
- a range of int values as specified or the empty range if
from >= toExclusive
-
rangeBy
Creates a List of int numbers starting fromfrom
, extending totoExclusive - 1
, withstep
.Examples:
List.rangeBy(1, 3, 1) // = List(1, 2) List.rangeBy(1, 4, 2) // = List(1, 3) List.rangeBy(4, 1, -2) // = List(4, 2) List.rangeBy(4, 1, 2) // = List()
- Parameters:
from
- the first numbertoExclusive
- the last number + 1step
- the step- Returns:
- a range of long values as specified or the empty range if
from >= toInclusive
andstep > 0
or
from <= toInclusive
andstep < 0
- Throws:
IllegalArgumentException
- ifstep
is zero
-
range
Creates a List of long numbers starting fromfrom
, extending totoExclusive - 1
.Examples:
List.range(0L, 0L) // = List() List.range(2L, 0L) // = List() List.range(-2L, 2L) // = List(-2L, -1L, 0L, 1L)
- Parameters:
from
- the first numbertoExclusive
- the last number + 1- Returns:
- a range of long values as specified or the empty range if
from >= toExclusive
-
rangeBy
Creates a List of long numbers starting fromfrom
, extending totoExclusive - 1
, withstep
.Examples:
List.rangeBy(1L, 3L, 1L) // = List(1L, 2L) List.rangeBy(1L, 4L, 2L) // = List(1L, 3L) List.rangeBy(4L, 1L, -2L) // = List(4L, 2L) List.rangeBy(4L, 1L, 2L) // = List()
- Parameters:
from
- the first numbertoExclusive
- the last number + 1step
- the step- Returns:
- a range of long values as specified or the empty range if
from >= toInclusive
andstep > 0
or
from <= toInclusive
andstep < 0
- Throws:
IllegalArgumentException
- ifstep
is zero
-
rangeClosed
-
rangeClosedBy
-
rangeClosedBy
-
rangeClosed
Creates a List of int numbers starting fromfrom
, extending totoInclusive
.Examples:
List.rangeClosed(0, 0) // = List(0) List.rangeClosed(2, 0) // = List() List.rangeClosed(-2, 2) // = List(-2, -1, 0, 1, 2)
- Parameters:
from
- the first numbertoInclusive
- the last number- Returns:
- a range of int values as specified or the empty range if
from > toInclusive
-
rangeClosedBy
Creates a List of int numbers starting fromfrom
, extending totoInclusive
, withstep
.Examples:
List.rangeClosedBy(1, 3, 1) // = List(1, 2, 3) List.rangeClosedBy(1, 4, 2) // = List(1, 3) List.rangeClosedBy(4, 1, -2) // = List(4, 2) List.rangeClosedBy(4, 1, 2) // = List()
- Parameters:
from
- the first numbertoInclusive
- the last numberstep
- the step- Returns:
- a range of int values as specified or the empty range if
from > toInclusive
andstep > 0
or
from < toInclusive
andstep < 0
- Throws:
IllegalArgumentException
- ifstep
is zero
-
rangeClosed
Creates a List of long numbers starting fromfrom
, extending totoInclusive
.Examples:
List.rangeClosed(0L, 0L) // = List(0L) List.rangeClosed(2L, 0L) // = List() List.rangeClosed(-2L, 2L) // = List(-2L, -1L, 0L, 1L, 2L)
- Parameters:
from
- the first numbertoInclusive
- the last number- Returns:
- a range of long values as specified or the empty range if
from > toInclusive
-
rangeClosedBy
Creates a List of long numbers starting fromfrom
, extending totoInclusive
, withstep
.Examples:
List.rangeClosedBy(1L, 3L, 1L) // = List(1L, 2L, 3L) List.rangeClosedBy(1L, 4L, 2L) // = List(1L, 3L) List.rangeClosedBy(4L, 1L, -2L) // = List(4L, 2L) List.rangeClosedBy(4L, 1L, 2L) // = List()
- Parameters:
from
- the first numbertoInclusive
- the last numberstep
- the step- Returns:
- a range of int values as specified or the empty range if
from > toInclusive
andstep > 0
or
from < toInclusive
andstep < 0
- Throws:
IllegalArgumentException
- ifstep
is zero
-
transpose
Transposes the rows and columns of aList
matrix.- Type Parameters:
T
- matrix element type- Parameters:
matrix
- to be transposed.- Returns:
- a transposed
List
matrix. - Throws:
IllegalArgumentException
- if the row lengths ofmatrix
differ.ex:
List.transpose(List(List(1,2,3), List(4,5,6))) → List(List(1,4), List(2,5), List(3,6))
-
unfoldRight
static <T,U> List<U> unfoldRight(T seed, Function<? super T, Option<Tuple2<? extends U, ? extends T>>> f) Creates a list from a seed value and a function. The function takes the seed at first. The function should returnNone
when it's done generating the list, otherwiseSome
Tuple
of the element for the next call and the value to add to the resulting list.Example:
List.unfoldRight(10, x -> x == 0 ? Option.none() : Option.of(new Tuple2<>(x, x-1))); // List(10, 9, 8, 7, 6, 5, 4, 3, 2, 1))
- Type Parameters:
T
- type of seedsU
- type of unfolded values- Parameters:
seed
- the start value for the iterationf
- the function to get the next step of the iteration- Returns:
- a list with the values built up by the iteration
- Throws:
NullPointerException
- iff
is null
-
unfoldLeft
static <T,U> List<U> unfoldLeft(T seed, Function<? super T, Option<Tuple2<? extends T, ? extends U>>> f) Creates a list from a seed value and a function. The function takes the seed at first. The function should returnNone
when it's done generating the list, otherwiseSome
Tuple
of the value to add to the resulting list and the element for the next call.Example:
List.unfoldLeft(10, x -> x == 0 ? Option.none() : Option.of(new Tuple2<>(x-1, x))); // List(1, 2, 3, 4, 5, 6, 7, 8, 9, 10))
- Type Parameters:
T
- type of seedsU
- type of unfolded values- Parameters:
seed
- the start value for the iterationf
- the function to get the next step of the iteration- Returns:
- a list with the values built up by the iteration
- Throws:
NullPointerException
- iff
is null
-
unfold
Creates a list from a seed value and a function. The function takes the seed at first. The function should returnNone
when it's done generating the list, otherwiseSome
Tuple
of the value to add to the resulting list and the element for the next call.Example:
List.unfold(10, x -> x == 0 ? Option.none() : Option.of(new Tuple2<>(x-1, x))); // List(1, 2, 3, 4, 5, 6, 7, 8, 9, 10))
- Type Parameters:
T
- type of seeds and unfolded values- Parameters:
seed
- the start value for the iterationf
- the function to get the next step of the iteration- Returns:
- a list with the values built up by the iteration
- Throws:
NullPointerException
- iff
is null
-
append
Description copied from interface:Seq
Appends an element to this. -
appendAll
Description copied from interface:Seq
Appends all given elements to this. -
asJava
Description copied from interface:Seq
Creates an immutableList
view on top of thisSeq
, i.e. calling mutators will result inUnsupportedOperationException
at runtime.The difference to conversion methods
toJava*()
is that- A view is created in O(1) (constant time) whereas conversion takes O(n) (linear time), with n = collection size.
- The operations on a view have the same performance characteristics than the underlying persistent Vavr collection whereas the performance characteristics of a converted collection are those of the Java standard collections.
java.util.List
view throwsUnsupportedOperationException
before checking method arguments. Java does handle this case inconsistently.- Specified by:
asJava
in interfaceSeq<T>
- Returns:
- A new immutable
Collection
view on thisTraversable
.
-
asJava
Description copied from interface:Seq
-
asJavaMutable
Description copied from interface:Seq
Creates a mutableList
view on top of thisSeq
, i.e. all mutator methods of theList
are implemented.- Specified by:
asJavaMutable
in interfaceSeq<T>
- Returns:
- A new mutable
Collection
view on thisTraversable
. - See Also:
-
asJavaMutable
Description copied from interface:Seq
- Specified by:
asJavaMutable
in interfaceLinearSeq<T>
- Specified by:
asJavaMutable
in interfaceSeq<T>
- Parameters:
action
- A side-effecting unit of work that operates on a mutablejava.util.List
view.- Returns:
- this instance, if only read operations are performed on the
java.util.List
view or a new instance of this type, if write operations are performed on thejava.util.List
view. - See Also:
-
collect
Description copied from interface:Traversable
Collects all elements that are in the domain of the givenpartialFunction
by mapping the elements to typeR
.More specifically, for each of this elements in iteration order first it is checked
If the elements makes it through that filter, the mapped instance is added to the result collectionpartialFunction.isDefinedAt(element)
Note:If thisR newElement = partialFunction.apply(element)
Traversable
is ordered (i.e. extendsOrdered
, the caller ofcollect
has to ensure that the elements are comparable (i.e. extendComparable
).- Specified by:
collect
in interfaceLinearSeq<T>
- Specified by:
collect
in interfaceSeq<T>
- Specified by:
collect
in interfaceTraversable<T>
- Type Parameters:
R
- The new element type- Parameters:
partialFunction
- A function that is not necessarily defined of all elements of this traversable.- Returns:
- A new
Traversable
instance containing elements of typeR
-
combinations
Description copied from interface:Seq
Returns the union of all combinations from k = 0 to length().Examples:
[].combinations() = [[]] [1,2,3].combinations() = [ [], // k = 0 [1], [2], [3], // k = 1 [1,2], [1,3], [2,3], // k = 2 [1,2,3] // k = 3 ]
- Specified by:
combinations
in interfaceLinearSeq<T>
- Specified by:
combinations
in interfaceSeq<T>
- Returns:
- the combinations of this
-
combinations
Description copied from interface:Seq
Returns the k-combination of this traversable, i.e. all subset of this of k distinct elements.- Specified by:
combinations
in interfaceLinearSeq<T>
- Specified by:
combinations
in interfaceSeq<T>
- Parameters:
k
- Size of subsets- Returns:
- the k-combination of this elements
- See Also:
-
crossProduct
Description copied from interface:Seq
Calculates the n-ary cartesian power (or cross product or simply product) of this.Example:
// = ((A,A), (A,B), (A,C), ..., (B,A), (B,B), ..., (Z,Y), (Z,Z)) CharSeq.rangeClosed('A', 'Z').crossProduct(2);
Cartesian power of negative value will return empty iterator.
Example:
// = () CharSeq.rangeClosed('A', 'Z').crossProduct(-1);
- Specified by:
crossProduct
in interfaceLinearSeq<T>
- Specified by:
crossProduct
in interfaceSeq<T>
- Parameters:
power
- the number of cartesian multiplications- Returns:
- A new Iterator representing the n-ary cartesian power of this
-
distinct
Description copied from interface:Traversable
Returns a new version of this which contains no duplicates. Elements are compared usingequals
. -
distinctBy
Description copied from interface:Traversable
Returns a new version of this which contains no duplicates. Elements are compared using the givencomparator
.- Specified by:
distinctBy
in interfaceLinearSeq<T>
- Specified by:
distinctBy
in interfaceSeq<T>
- Specified by:
distinctBy
in interfaceTraversable<T>
- Parameters:
comparator
- A comparator- Returns:
- a new
Traversable
containing this elements without duplicates
-
distinctBy
Description copied from interface:Traversable
Returns a new version of this which contains no duplicates. Elements mapped to keys which are compared usingequals
.The elements of the result are determined in the order of their occurrence - first match wins.
- Specified by:
distinctBy
in interfaceLinearSeq<T>
- Specified by:
distinctBy
in interfaceSeq<T>
- Specified by:
distinctBy
in interfaceTraversable<T>
- Type Parameters:
U
- key type- Parameters:
keyExtractor
- A key extractor- Returns:
- a new
Traversable
containing this elements without duplicates
-
drop
Description copied from interface:Traversable
Drops the first n elements of this or all elements, if this length < n.- Specified by:
drop
in interfaceLinearSeq<T>
- Specified by:
drop
in interfaceSeq<T>
- Specified by:
drop
in interfaceTraversable<T>
- Parameters:
n
- The number of elements to drop.- Returns:
- a new instance consisting of all elements of this except the first n ones, or else the empty instance, if this has less than n elements.
-
dropUntil
Description copied from interface:Traversable
Drops elements until the predicate holds for the current element.- Specified by:
dropUntil
in interfaceLinearSeq<T>
- Specified by:
dropUntil
in interfaceSeq<T>
- Specified by:
dropUntil
in interfaceTraversable<T>
- Parameters:
predicate
- A condition tested subsequently for this elements.- Returns:
- a new instance consisting of all elements starting from the first one which does satisfy the given predicate.
-
dropWhile
Description copied from interface:Traversable
Drops elements while the predicate holds for the current element.Note: This is essentially the same as
dropUntil(predicate.negate())
. It is intended to be used with method references, which cannot be negated directly.- Specified by:
dropWhile
in interfaceLinearSeq<T>
- Specified by:
dropWhile
in interfaceSeq<T>
- Specified by:
dropWhile
in interfaceTraversable<T>
- Parameters:
predicate
- A condition tested subsequently for this elements.- Returns:
- a new instance consisting of all elements starting from the first one which does not satisfy the given predicate.
-
dropRight
Description copied from interface:Traversable
Drops the last n elements of this or all elements, if this length < n.- Specified by:
dropRight
in interfaceLinearSeq<T>
- Specified by:
dropRight
in interfaceSeq<T>
- Specified by:
dropRight
in interfaceTraversable<T>
- Parameters:
n
- The number of elements to drop.- Returns:
- a new instance consisting of all elements of this except the last n ones, or else the empty instance, if this has less than n elements.
-
dropRightUntil
Description copied from interface:Seq
Drops elements until the predicate holds for the current element, starting from the end.- Specified by:
dropRightUntil
in interfaceLinearSeq<T>
- Specified by:
dropRightUntil
in interfaceSeq<T>
- Parameters:
predicate
- A condition tested subsequently for this elements, starting from the end.- Returns:
- a new instance consisting of all elements until and including the last one which does satisfy the given predicate.
-
dropRightWhile
Description copied from interface:Seq
Drops elements while the predicate holds for the current element, starting from the end.Note: This is essentially the same as
dropRightUntil(predicate.negate())
. It is intended to be used with method references, which cannot be negated directly.- Specified by:
dropRightWhile
in interfaceLinearSeq<T>
- Specified by:
dropRightWhile
in interfaceSeq<T>
- Parameters:
predicate
- A condition tested subsequently for this elements, starting from the end.- Returns:
- a new instance consisting of all elements until and including the last one which does not satisfy the given predicate.
-
filter
Description copied from interface:Traversable
Returns a new traversable consisting of all elements which satisfy the given predicate. -
reject
Description copied from interface:Traversable
Returns a new traversable consisting of all elements which do not satisfy the given predicate.The default implementation is equivalent to
filter(predicate.negate()
-
flatMap
Description copied from interface:Traversable
FlatMaps this Traversable. -
get
Description copied from interface:Seq
Returns the element at the specified index. -
groupBy
Description copied from interface:Traversable
Groups this elements by classifying the elements.- Specified by:
groupBy
in interfaceLinearSeq<T>
- Specified by:
groupBy
in interfaceSeq<T>
- Specified by:
groupBy
in interfaceTraversable<T>
- Type Parameters:
C
- classified class type- Parameters:
classifier
- A function which classifies elements into classes- Returns:
- A Map containing the grouped elements
- See Also:
-
grouped
Description copied from interface:Traversable
Groups thisTraversable
into fixed size blocks.Let length be the length of this Iterable. Then grouped is defined as follows:
- If
this.isEmpty()
, the resultingIterator
is empty. - If
size <= length
, the resultingIterator
will containlength / size
blocks of sizesize
and maybe a non-empty block of sizelength % size
, if there are remaining elements. - If
size > length
, the resultingIterator
will contain one block of sizelength
.
[].grouped(1) = [] [].grouped(0) throws [].grouped(-1) throws [1,2,3,4].grouped(2) = [[1,2],[3,4]] [1,2,3,4,5].grouped(2) = [[1,2],[3,4],[5]] [1,2,3,4].grouped(5) = [[1,2,3,4]]
grouped(int)
is a special case of Traversable.sliding(int, int), i.e.grouped(size)
is the same assliding(size, size)
. - If
-
hasDefiniteSize
default boolean hasDefiniteSize()Description copied from interface:Traversable
Checks if this Traversable is known to have a finite size.This method should be implemented by classes only, i.e. not by interfaces.
- Specified by:
hasDefiniteSize
in interfaceTraversable<T>
- Returns:
- true, if this Traversable is known to have a finite size, false otherwise.
-
indexOf
Description copied from interface:Seq
Returns the index of the first occurrence of the given element after or at some start index or -1 if this does not contain the given element. -
init
Description copied from interface:Traversable
Dual of Traversable.tail(), returning all elements except the last. -
initOption
Description copied from interface:Traversable
Dual of Traversable.tailOption(), returning all elements except the last asOption
.- Specified by:
initOption
in interfaceLinearSeq<T>
- Specified by:
initOption
in interfaceSeq<T>
- Specified by:
initOption
in interfaceTraversable<T>
- Returns:
Some(traversable)
orNone
if this is empty.
-
length
int length()Description copied from interface:Traversable
Computes the number of elements of this Traversable.Same as
Traversable.size()
.- Specified by:
length
in interfaceTraversable<T>
- Returns:
- the number of elements
-
insert
Description copied from interface:Seq
Inserts the given element at the specified index. -
insertAll
Description copied from interface:Seq
Inserts the given elements at the specified index. -
intersperse
Description copied from interface:Seq
Inserts an element between all elements of this Traversable.- Specified by:
intersperse
in interfaceLinearSeq<T>
- Specified by:
intersperse
in interfaceSeq<T>
- Parameters:
element
- An element.- Returns:
- an interspersed version of this
-
isTraversableAgain
default boolean isTraversableAgain()Description copied from interface:Traversable
Checks if this Traversable can be repeatedly traversed.This method should be implemented by classes only, i.e. not by interfaces.
- Specified by:
isTraversableAgain
in interfaceTraversable<T>
- Returns:
- true, if this Traversable is known to be traversable repeatedly, false otherwise.
-
last
Description copied from interface:Traversable
Dual of Traversable.head(), returning the last element.- Specified by:
last
in interfaceTraversable<T>
- Returns:
- the last element.
-
lastIndexOf
Description copied from interface:Seq
Returns the index of the last occurrence of the given element before or at a given end index or -1 if this does not contain the given element.- Specified by:
lastIndexOf
in interfaceSeq<T>
- Parameters:
element
- an elementend
- the end index- Returns:
- the index of the last occurrence of the given element
-
map
Description copied from interface:Traversable
Maps the elements of thisTraversable
to elements of a new type preserving their order, if any. -
orElse
Description copied from interface:Traversable
Returns thisTraversable
if it is nonempty, otherwise return the alternative. -
orElse
Description copied from interface:Traversable
Returns thisTraversable
if it is nonempty, otherwise return the result of evaluating supplier. -
padTo
Description copied from interface:Seq
A copy of this sequence with an element appended until a given target length is reached.Note: lazily-evaluated Seq implementations need to process all elements in order to gather the overall length.
- Specified by:
padTo
in interfaceLinearSeq<T>
- Specified by:
padTo
in interfaceSeq<T>
- Parameters:
length
- the target lengthelement
- the padding element- Returns:
- a new sequence consisting of all elements of this sequence followed by the minimal number
of occurrences of
element
so that the resulting sequence has a length of at leastlength
.
-
leftPadTo
Description copied from interface:Seq
A copy of this sequence with an element prepended until a given target length is reached.Note: lazily-evaluated Seq implementations need to process all elements in order to gather the overall length.
- Specified by:
leftPadTo
in interfaceSeq<T>
- Parameters:
length
- the target lengthelement
- the padding element- Returns:
- a new sequence consisting of all elements of this sequence prepended by the minimal number
of occurrences of
element
so that the resulting sequence has a length of at leastlength
.
-
patch
Description copied from interface:Seq
Produces a new list where a slice of elements in this list is replaced by another sequence. -
partition
Description copied from interface:Traversable
Creates a partition of thisTraversable
by splitting this elements in two in distinct traversables according to a predicate.- Specified by:
partition
in interfaceLinearSeq<T>
- Specified by:
partition
in interfaceSeq<T>
- Specified by:
partition
in interfaceTraversable<T>
- Parameters:
predicate
- A predicate which classifies an element if it is in the first or the second traversable.- Returns:
- A disjoint union of two traversables. The first
Traversable
contains all elements that satisfy the givenpredicate
, the secondTraversable
contains all elements that don't. The original order of elements is preserved.
-
peek
Returns the head element without modifying the List.- Returns:
- the first element
- Throws:
NoSuchElementException
- if this List is empty
-
peekOption
Returns the head element without modifying the List.- Returns:
None
if this List is empty, otherwise aSome
containing the head element
-
peek
Performs an action on the head element of thisList
. -
permutations
Description copied from interface:Seq
Computes all unique permutations.Example:
[].permutations() = [] [1,2,3].permutations() = [ [1,2,3], [1,3,2], [2,1,3], [2,3,1], [3,1,2], [3,2,1] ]
- Specified by:
permutations
in interfaceLinearSeq<T>
- Specified by:
permutations
in interfaceSeq<T>
- Returns:
- this unique permutations
-
pop
Removes the head element from this List.- Returns:
- the elements of this List without the head element
- Throws:
NoSuchElementException
- if this List is empty
-
popOption
Removes the head element from this List.- Returns:
None
if this List is empty, otherwise aSome
containing the elements of this List without the head element
-
pop2
Removes the head element from this List.- Returns:
- a tuple containing the head element and the remaining elements of this List
- Throws:
NoSuchElementException
- if this List is empty
-
pop2Option
Removes the head element from this List.- Returns:
None
if this List is empty, otherwiseSome
Tuple
containing the head element and the remaining elements of this List
-
prepend
Description copied from interface:Seq
Prepends an element to this. -
prependAll
Description copied from interface:Seq
Prepends all given elements to this.- Specified by:
prependAll
in interfaceLinearSeq<T>
- Specified by:
prependAll
in interfaceSeq<T>
- Parameters:
elements
- An Iterable of elements- Returns:
- A new Seq containing the given elements prepended to this elements
-
push
Pushes a new element on top of this List.- Parameters:
element
- The new element- Returns:
- a new
List
instance, containing the new element on top of this List
-
push
Pushes the given elements on top of this List. A List has LIFO order, i.e. the last of the given elements is the first which will be retrieved.- Parameters:
elements
- Elements, may be empty- Returns:
- a new
List
instance, containing the new elements on top of this List - Throws:
NullPointerException
- if elements is null
-
pushAll
Pushes the given elements on top of this List. A List has LIFO order, i.e. the last of the given elements is the first which will be retrieved.- Parameters:
elements
- An Iterable of elements, may be empty- Returns:
- a new
List
instance, containing the new elements on top of this List - Throws:
NullPointerException
- if elements is null
-
remove
Description copied from interface:Seq
Removes the first occurrence of the given element. -
removeFirst
Description copied from interface:Seq
Removes the first occurrence that satisfy predicate- Specified by:
removeFirst
in interfaceLinearSeq<T>
- Specified by:
removeFirst
in interfaceSeq<T>
- Parameters:
predicate
- an predicate- Returns:
- a new Seq
-
removeLast
Description copied from interface:Seq
Removes the last occurrence that satisfy predicate- Specified by:
removeLast
in interfaceLinearSeq<T>
- Specified by:
removeLast
in interfaceSeq<T>
- Parameters:
predicate
- an predicate- Returns:
- a new Seq
-
removeAt
Description copied from interface:Seq
Removes the element at the specified position in this sequence. Shifts any subsequent elements to the left (subtracts one from their indices). -
removeAll
Description copied from interface:Seq
Removes all occurrences of the given element. -
removeAll
Description copied from interface:Seq
Removes all occurrences of the given elements. -
removeAll
Deprecated.Description copied from interface:Seq
Returns a new Seq consisting of all elements which do not satisfy the given predicate. -
replace
Description copied from interface:Traversable
Replaces the first occurrence (if exists) of the given currentElement with newElement.- Specified by:
replace
in interfaceLinearSeq<T>
- Specified by:
replace
in interfaceSeq<T>
- Specified by:
replace
in interfaceTraversable<T>
- Parameters:
currentElement
- An element to be substituted.newElement
- A replacement for currentElement.- Returns:
- a Traversable containing all elements of this where the first occurrence of currentElement is replaced with newElement.
-
replaceAll
Description copied from interface:Traversable
Replaces all occurrences of the given currentElement with newElement.- Specified by:
replaceAll
in interfaceLinearSeq<T>
- Specified by:
replaceAll
in interfaceSeq<T>
- Specified by:
replaceAll
in interfaceTraversable<T>
- Parameters:
currentElement
- An element to be substituted.newElement
- A replacement for currentElement.- Returns:
- a Traversable containing all elements of this where all occurrences of currentElement are replaced with newElement.
-
retainAll
Description copied from interface:Traversable
Keeps all occurrences of the given elements from this. -
reverse
Description copied from interface:Seq
Reverses the order of elements. -
rotateLeft
Description copied from interface:Seq
Circular rotates the elements by the specified distance to the left direction.// = List(3, 4, 5, 1, 2) List.of(1, 2, 3, 4, 5).rotateLeft(2);
- Specified by:
rotateLeft
in interfaceLinearSeq<T>
- Specified by:
rotateLeft
in interfaceSeq<T>
- Parameters:
n
- distance of left rotation- Returns:
- the rotated elements.
-
rotateRight
Description copied from interface:Seq
Circular rotates the elements by the specified distance to the right direction.// = List(4, 5, 1, 2, 3) List.of(1, 2, 3, 4, 5).rotateRight(2);
- Specified by:
rotateRight
in interfaceLinearSeq<T>
- Specified by:
rotateRight
in interfaceSeq<T>
- Parameters:
n
- distance of right rotation- Returns:
- the rotated elements.
-
scan
Description copied from interface:Traversable
Computes a prefix scan of the elements of the collection. Note: The neutral element z may be applied more than once.- Specified by:
scan
in interfaceLinearSeq<T>
- Specified by:
scan
in interfaceSeq<T>
- Specified by:
scan
in interfaceTraversable<T>
- Parameters:
zero
- neutral element for the operator opoperation
- the associative operator for the scan- Returns:
- a new traversable collection containing the prefix scan of the elements in this traversable collection
-
scanLeft
Description copied from interface:Traversable
Produces a collection containing cumulative results of applying the operator going left to right. Note: will not terminate for infinite-sized collections. Note: might return different results for different runs, unless the underlying collection type is ordered.- Specified by:
scanLeft
in interfaceLinearSeq<T>
- Specified by:
scanLeft
in interfaceSeq<T>
- Specified by:
scanLeft
in interfaceTraversable<T>
- Type Parameters:
U
- the type of the elements in the resulting collection- Parameters:
zero
- the initial valueoperation
- the binary operator applied to the intermediate result and the element- Returns:
- collection with intermediate results
-
scanRight
Description copied from interface:Traversable
Produces a collection containing cumulative results of applying the operator going right to left. The head of the collection is the last cumulative result. Note: will not terminate for infinite-sized collections. Note: might return different results for different runs, unless the underlying collection type is ordered.- Specified by:
scanRight
in interfaceLinearSeq<T>
- Specified by:
scanRight
in interfaceSeq<T>
- Specified by:
scanRight
in interfaceTraversable<T>
- Type Parameters:
U
- the type of the elements in the resulting collection- Parameters:
zero
- the initial valueoperation
- the binary operator applied to the intermediate result and the element- Returns:
- collection with intermediate results
-
shuffle
Description copied from interface:Seq
Randomize the order of the elements in the current sequence. -
slice
Description copied from interface:Seq
Returns a Seq that is a slice of this. The slice begins with the element at the specifiedbeginIndex
and extends to the element at indexendIndex - 1
.Examples:
List.of(1, 2, 3, 4).slice(1, 3); // = (2, 3) List.of(1, 2, 3, 4).slice(0, 4); // = (1, 2, 3, 4) List.of(1, 2, 3, 4).slice(2, 2); // = () List.of(1, 2).slice(1, 0); // = () List.of(1, 2).slice(-10, 10); // = (1, 2)
Seq.subSequence(int, int)
which throws in some cases instead of returning a sequence. -
slideBy
Description copied from interface:Traversable
Slides a non-overlapping window of a variable size over thisTraversable
.Each window contains elements with the same class, as determined by
classifier
. Two consecutive values in thisTraversable
will be in the same window only ifclassifier
returns equal values for them. Otherwise, the values will constitute the last element of the previous window and the first element of the next window.Examples:
[].slideBy(Function.identity()) = [] [1,2,3,4,4,5].slideBy(Function.identity()) = [[1],[2],[3],[4,4],[5]] [1,2,3,10,12,5,7,20,29].slideBy(x -> x/10) = [[1,2,3],[10,12],[5,7],[20,29]]
-
sliding
Description copied from interface:Traversable
Slides a window of a specificsize
and step size 1 over thisTraversable
by callingTraversable.sliding(int, int)
. -
sliding
Description copied from interface:Traversable
Slides a window of a specificsize
andstep
size over thisTraversable
.Examples:
[].sliding(1,1) = [] [1,2,3,4,5].sliding(2,3) = [[1,2],[4,5]] [1,2,3,4,5].sliding(2,4) = [[1,2],[5]] [1,2,3,4,5].sliding(2,5) = [[1,2]] [1,2,3,4].sliding(5,3) = [[1,2,3,4],[4]]
-
sorted
Description copied from interface:Seq
Sorts this elements according to their natural order. If this elements are notComparable
, ajava.lang.ClassCastException
may be thrown. -
sorted
Description copied from interface:Seq
Sorts this elements according to the providedComparator
. If this elements are notComparable
, ajava.lang.ClassCastException
may be thrown. -
sortBy
Description copied from interface:Seq
Sorts this elements by comparing the elements in a different domain, using the givenmapper
. -
sortBy
default <U> List<T> sortBy(Comparator<? super U> comparator, Function<? super T, ? extends U> mapper) Description copied from interface:Seq
Sorts this elements by comparing the elements in a different domain, using the givenmapper
. -
span
Description copied from interface:Traversable
Returns a tuple where the first element is the longest prefix of elements that satisfy the givenpredicate
and the second element is the remainder. -
splitAt
Description copied from interface:Seq
Splits a Seq at the specified index. The result ofsplitAt(n)
is equivalent toTuple.of(take(n), drop(n))
. -
splitAt
Description copied from interface:Seq
Splits a sequence at the first element which satisfies thePredicate
, e.g. Tuple(init, element+tail). -
splitAtInclusive
Description copied from interface:Seq
Splits a sequence at the first element which satisfies thePredicate
, e.g. Tuple(init+element, tail).- Specified by:
splitAtInclusive
in interfaceSeq<T>
- Parameters:
predicate
- An predicate- Returns:
- A
Tuple
containing divided sequences
-
stringPrefix
Description copied from interface:Value
Returns the name of this Value type, which is used by toString().- Specified by:
stringPrefix
in interfaceValue<T>
- Returns:
- This type name.
-
subSequence
Description copied from interface:Seq
Returns a Seq that is a subsequence of this. The subsequence begins with the element at the specifiedbeginIndex
and extends to the end of this Seq.Examples:
List.of(1, 2).subSequence(0); // = (1, 2) List.of(1, 2).subSequence(1); // = (2) List.of(1, 2).subSequence(2); // = () List.of(1, 2).subSequence(10); // throws IndexOutOfBoundsException List.of(1, 2).subSequence(-10); // throws IndexOutOfBoundsException
Seq.drop(int)
which is similar but does not throw.- Specified by:
subSequence
in interfaceLinearSeq<T>
- Specified by:
subSequence
in interfaceSeq<T>
- Parameters:
beginIndex
- the beginning index, inclusive- Returns:
- the specified subsequence
-
subSequence
Description copied from interface:Seq
Returns a Seq that is a subsequence of this. The subsequence begins with the element at the specifiedbeginIndex
and extends to the element at indexendIndex - 1
.Examples:
List.of(1, 2, 3, 4).subSequence(1, 3); // = (2, 3) List.of(1, 2, 3, 4).subSequence(0, 4); // = (1, 2, 3, 4) List.of(1, 2, 3, 4).subSequence(2, 2); // = () List.of(1, 2).subSequence(1, 0); // throws IndexOutOfBoundsException List.of(1, 2).subSequence(-10, 1); // throws IndexOutOfBoundsException List.of(1, 2).subSequence(0, 10); // throws IndexOutOfBoundsException
Seq.slice(int, int)
which returns an empty sequence instead of throwing.- Specified by:
subSequence
in interfaceLinearSeq<T>
- Specified by:
subSequence
in interfaceSeq<T>
- Parameters:
beginIndex
- the beginning index, inclusiveendIndex
- the end index, exclusive- Returns:
- the specified subsequence
-
tail
Description copied from interface:Traversable
Drops the first element of a non-empty Traversable. -
tailOption
Description copied from interface:Traversable
Drops the first element of a non-empty Traversable and returns anOption
.- Specified by:
tailOption
in interfaceLinearSeq<T>
- Specified by:
tailOption
in interfaceSeq<T>
- Specified by:
tailOption
in interfaceTraversable<T>
- Returns:
Some(traversable)
orNone
if this is empty.
-
take
Description copied from interface:Traversable
Takes the first n elements of this or all elements, if this length < n.The result is equivalent to
sublist(0, max(0, min(length(), n)))
but does not throw ifn < 0
orn > length()
.In the case of
n < 0
the empty instance is returned, in the case ofn > length()
this is returned. -
takeUntil
Description copied from interface:Traversable
Takes elements until the predicate holds for the current element.Note: This is essentially the same as
takeWhile(predicate.negate())
. It is intended to be used with method references, which cannot be negated directly.- Specified by:
takeUntil
in interfaceLinearSeq<T>
- Specified by:
takeUntil
in interfaceSeq<T>
- Specified by:
takeUntil
in interfaceTraversable<T>
- Parameters:
predicate
- A condition tested subsequently for this elements.- Returns:
- a new instance consisting of all elements before the first one which does satisfy the given predicate.
-
takeWhile
Description copied from interface:Traversable
Takes elements while the predicate holds for the current element.- Specified by:
takeWhile
in interfaceLinearSeq<T>
- Specified by:
takeWhile
in interfaceSeq<T>
- Specified by:
takeWhile
in interfaceTraversable<T>
- Parameters:
predicate
- A condition tested subsequently for the contained elements.- Returns:
- a new instance consisting of all elements before the first one which does not satisfy the given predicate.
-
takeRight
Description copied from interface:Traversable
Takes the last n elements of this or all elements, if this length < n.The result is equivalent to
sublist(max(0, min(length(), length() - n)), n)
, i.e. takeRight will not throw ifn < 0
orn > length()
.In the case of
n < 0
the empty instance is returned, in the case ofn > length()
this is returned.- Specified by:
takeRight
in interfaceLinearSeq<T>
- Specified by:
takeRight
in interfaceSeq<T>
- Specified by:
takeRight
in interfaceTraversable<T>
- Parameters:
n
- The number of elements to take.- Returns:
- A new instance consisting of the last n elements of this or all elements, if this has less than n elements.
-
takeRightUntil
Description copied from interface:Seq
Takes elements until the predicate holds for the current element, starting from the end.- Specified by:
takeRightUntil
in interfaceLinearSeq<T>
- Specified by:
takeRightUntil
in interfaceSeq<T>
- Parameters:
predicate
- A condition tested subsequently for this elements, starting from the end.- Returns:
- a new instance consisting of all elements after the last one which does satisfy the given predicate.
-
takeRightWhile
Description copied from interface:Seq
Takes elements while the predicate holds for the current element, starting from the end.Note: This is essentially the same as
takeRightUntil(predicate.negate())
. It is intended to be used with method references, which cannot be negated directly.- Specified by:
takeRightWhile
in interfaceLinearSeq<T>
- Specified by:
takeRightWhile
in interfaceSeq<T>
- Parameters:
predicate
- A condition tested subsequently for this elements, starting from the end.- Returns:
- a new instance consisting of all elements after the last one which does not satisfy the given predicate.
-
transform
Transforms thisList
.- Type Parameters:
U
- Type of transformation result- Parameters:
f
- A transformation- Returns:
- An instance of type
U
- Throws:
NullPointerException
- iff
is null
-
unzip
default <T1,T2> Tuple2<List<T1>,List<T2>> unzip(Function<? super T, Tuple2<? extends T1, ? extends T2>> unzipper) Description copied from interface:Traversable
Unzips this elements by mapping this elements to pairs which are subsequently split into two distinct sets.- Specified by:
unzip
in interfaceLinearSeq<T>
- Specified by:
unzip
in interfaceSeq<T>
- Specified by:
unzip
in interfaceTraversable<T>
- Type Parameters:
T1
- 1st element type of a pair returned by unzipperT2
- 2nd element type of a pair returned by unzipper- Parameters:
unzipper
- a function which converts elements of this to pairs- Returns:
- A pair of set containing elements split by unzipper
-
unzip3
default <T1,T2, Tuple3<List<T1>,T3> List<T2>, unzip3List<T3>> (Function<? super T, Tuple3<? extends T1, ? extends T2, ? extends T3>> unzipper) Description copied from interface:Traversable
Unzips this elements by mapping this elements to triples which are subsequently split into three distinct sets.- Specified by:
unzip3
in interfaceSeq<T>
- Specified by:
unzip3
in interfaceTraversable<T>
- Type Parameters:
T1
- 1st element type of a triplet returned by unzipperT2
- 2nd element type of a triplet returned by unzipperT3
- 3rd element type of a triplet returned by unzipper- Parameters:
unzipper
- a function which converts elements of this to pairs- Returns:
- A triplet of set containing elements split by unzipper
-
update
Description copied from interface:Seq
Updates the given element at the specified index. -
update
Description copied from interface:Seq
Updates the given element at the specified index using the specified function. -
zip
Description copied from interface:Traversable
Returns a traversable formed from this traversable and another Iterable collection by combining corresponding elements in pairs. If one of the two iterables is longer than the other, its remaining elements are ignored.The length of the returned traversable is the minimum of the lengths of this traversable and
that
iterable.- Specified by:
zip
in interfaceLinearSeq<T>
- Specified by:
zip
in interfaceSeq<T>
- Specified by:
zip
in interfaceTraversable<T>
- Type Parameters:
U
- The type of the second half of the returned pairs.- Parameters:
that
- The Iterable providing the second half of each result pair.- Returns:
- a new traversable containing pairs consisting of corresponding elements of this traversable and
that
iterable.
-
zipWith
default <U,R> List<R> zipWith(Iterable<? extends U> that, BiFunction<? super T, ? super U, ? extends R> mapper) Description copied from interface:Traversable
Returns a traversable formed from this traversable and another Iterable collection by mapping elements. If one of the two iterables is longer than the other, its remaining elements are ignored.The length of the returned traversable is the minimum of the lengths of this traversable and
that
iterable.- Specified by:
zipWith
in interfaceLinearSeq<T>
- Specified by:
zipWith
in interfaceSeq<T>
- Specified by:
zipWith
in interfaceTraversable<T>
- Type Parameters:
U
- The type of the second parameter of the mapper.R
- The type of the mapped elements.- Parameters:
that
- The Iterable providing the second parameter of the mapper.mapper
- a mapper.- Returns:
- a new traversable containing mapped elements of this traversable and
that
iterable.
-
zipAll
Description copied from interface:Traversable
Returns a traversable formed from this traversable and another Iterable by combining corresponding elements in pairs. If one of the two collections is shorter than the other, placeholder elements are used to extend the shorter collection to the length of the longer.The length of the returned traversable is the maximum of the lengths of this traversable and
that
iterable.Special case: if this traversable is shorter than that elements, and that elements contains duplicates, the resulting traversable may be shorter than the maximum of the lengths of this and that because a traversable contains an element at most once.
If this Traversable is shorter than that, thisElem values are used to fill the result. If that is shorter than this Traversable, thatElem values are used to fill the result.
- Specified by:
zipAll
in interfaceLinearSeq<T>
- Specified by:
zipAll
in interfaceSeq<T>
- Specified by:
zipAll
in interfaceTraversable<T>
- Type Parameters:
U
- The type of the second half of the returned pairs.- Parameters:
that
- The Iterable providing the second half of each result pair.thisElem
- The element to be used to fill up the result if this traversable is shorter than that.thatElem
- The element to be used to fill up the result if that is shorter than this traversable.- Returns:
- A new traversable containing pairs consisting of corresponding elements of this traversable and that.
-
zipWithIndex
Description copied from interface:Traversable
Zips this traversable with its indices.- Specified by:
zipWithIndex
in interfaceLinearSeq<T>
- Specified by:
zipWithIndex
in interfaceSeq<T>
- Specified by:
zipWithIndex
in interfaceTraversable<T>
- Returns:
- A new traversable containing all elements of this traversable paired with their index, starting with 0.
-
zipWithIndex
Description copied from interface:Traversable
Zips this traversable with its indices by applying mapper provided.- Specified by:
zipWithIndex
in interfaceLinearSeq<T>
- Specified by:
zipWithIndex
in interfaceSeq<T>
- Specified by:
zipWithIndex
in interfaceTraversable<T>
- Type Parameters:
U
- The type of the mapped elements.- Parameters:
mapper
- a mapper.- Returns:
- a new traversable containing elements of this traversable, zipped with indices, and mapped with mapper provided.
-