Package fj.data

Class Array<A>

java.lang.Object
fj.data.Array<A>
All Implemented Interfaces:
Iterable<A>

public final class Array<A> extends Object implements Iterable<A>
Provides an interface to arrays.
Version:
%build.number%
  • Nested Class Summary

    Nested Classes
    Modifier and Type
    Class
    Description
    static final class 
    Projects an array by providing only operations which do not mutate.
  • Field Summary

    Fields
    Modifier and Type
    Field
    Description
    private final Object[]
     
  • Constructor Summary

    Constructors
    Modifier
    Constructor
    Description
    private
     
  • Method Summary

    Modifier and Type
    Method
    Description
    append(Array<A> aas)
    Appends the given array to this array.
    <B> Array<B>
    apply(Array<F<A,B>> lf)
    Performs function application within an array (applicative functor pattern).
    Returns a copy of the underlying primitive array.
    static <A> Array<A>
    array(A... as)
    Constructs an array from the given elements.
    A[]
    array(Class<A[]> c)
    Returns a copy of the underlying primitive array.
    static <A> Array<A>
    arrayArray(A... as)
    Returns a copy of the underlying primitive array.
    Projects an unmodifiable list view of this array.
    <B, C> Array<C>
    bind(Array<B> sb, F<A,F<B,C>> f)
    Binds the given function across each element of this array and the given array with a final join.
    <B, C> Array<C>
    bind(Array<B> sb, F2<A,B,C> f)
    Binds the given function across each element of this array and the given array with a final join.
    <B> Array<B>
    bind(F<A,Array<B>> f)
    Binds the given function across each element of this array with a final join.
    static <T> T[]
    copyOf(T[] a, int len)
     
    static <T, U> T[]
    copyOf(U[] a, int len, Class<? extends T[]> newType)
     
    static char[]
    copyOfRange(char[] a, int from, int to)
     
    static <A> Array<A>
    Returns an empty array.
    boolean
     
    boolean
    Returns true if the predicate holds for at least one of the elements of this array, false otherwise (false for the empty array).
    Filters elements from this array by returning only elements which produce true when the given function is applied to them.
    Finds the first occurrence of an element that matches the given predicate or no value if no elements match.
    <B> B
    foldLeft(F<B,F<A,B>> f, B b)
    Performs a left-fold reduction across this array.
    <B> B
    foldLeft(F2<B,A,B> f, B b)
    Performs a left-fold reduction across this array.
    <B> B
    foldRight(F<A,F<B,B>> f, B b)
    Performs a right-fold reduction across this array.
    <B> B
    foldRight(F2<A,B,B> f, B b)
    Performs a right-fold reduction across this array.
    boolean
    Returns true if the predicate holds for all of the elements of this array, false otherwise (true for the empty array).
    Performs a side-effect for each element of this array.
    void
    Performs a side-effect for each element of this array.
    get(int index)
    Returns the element at the given index if it exists, fails otherwise.
    int
     
     
    boolean
    Returns true is this array is empty, false otherwise.
    boolean
    Returns false is this array is empty, true otherwise.
    static <A> Array<A>
    Takes the given iterable to an array.
    Returns an iterator for this array.
    static <A> Array<A>
    Creates an Array from the iterator.
    static <A> F<Array<Array<A>>,Array<A>>
    A first-class version of join
    static <A> Array<A>
    join(Array<Array<A>> o)
    Joins the given array of arrays using a bind operation.
    int
    Returns the length of this array.
    static <A, B> F<F<A,B>,F<Array<A>,Array<B>>>
    map()
    First-class map function for Arrays.
    <B> Array<B>
    map(F<A,B> f)
    Maps the given function across this array.
    (package private) static <A> Array<A>
    Unsafe package-private constructor.
    static Array<Integer>
    range(int from, int to)
    Returns an array of integers from the given from value (inclusive) to the given to value (exclusive).
    Reverse this array in constant stack space.
    <B> Array<B>
    scanLeft(F<B,F<A,B>> f, B b)
    Performs a fold left accummulating and returns an array of the intermediate results.
    <B> Array<B>
    scanLeft(F2<B,A,B> f, B b)
    Performs a left-fold accummulating and returns an array of the intermediate results.
    scanLeft1(F<A,F<A,A>> f)
    Performs a left-fold accummulating using first array element as a starting value and returns an array of the intermediate results.
    Performs a left-fold accummulating using first array element as a starting value and returns an array of the intermediate results.
    <B> Array<B>
    scanRight(F<A,F<B,B>> f, B b)
    Performs a right-fold accummulating and returns an array of the intermediate results.
    <B> Array<B>
    scanRight(F2<A,B,B> f, B b)
    Performs a right-fold accummulating and returns an array of the intermediate results.
    scanRight1(F<A,F<A,A>> f)
    Performs a right-fold accummulating using last array element as a starting value and returns an array of the intermediate results.
    Performs a right-fold accummulating using last array element as a starting value and returns an array of the intermediate results.
    <B> Array<B>
    sequence(Array<B> bs)
    Performs a bind across each array element, but ignores the element value each time.
    set(int index, A a)
    Sets the element at the given index to the given value.
    static <A> Array<A>
    single(A a)
    Constructs a singleton array.
    Projects an immutable collection of this array.
    <X> Either<X,A>
    toEither(F0<X> x)
    Returns an either projection of this array; the given argument in Left if empty, or the first element in Right.
    Returns a java.util.ArrayList projection of this array.
    Returns a list projection of this array.
    Returns an option projection of this array; None if empty, or the first element in Some.
    Returns a stream projection of this array.
     
    static <A, B> P2<Array<A>,Array<B>>
    unzip(Array<P2<A,B>> xs)
    Transforms an array of pairs into an array of first components and an array of second components.
    static <A> F<A[],Array<A>>
    First-class wrapper function for arrays.
    <B> Array<P2<A,B>>
    zip(Array<B> bs)
    Zips this array with the given array to produce an array of pairs.
    Zips this array with the index of its element as a pair.
    <B, C> Array<C>
    zipWith(Array<B> bs, F<A,F<B,C>> f)
    Zips this array with the given array using the given function to produce a new array.
    <B, C> Array<C>
    zipWith(Array<B> bs, F2<A,B,C> f)
    Zips this array with the given array using the given function to produce a new array.

    Methods inherited from class java.lang.Object

    clone, finalize, getClass, notify, notifyAll, wait, wait, wait

    Methods inherited from interface java.lang.Iterable

    forEach, spliterator
  • Field Details

    • a

      private final Object[] a
  • Constructor Details

    • Array

      private Array(Object[] a)
  • Method Details

    • iterator

      public Iterator<A> iterator()
      Returns an iterator for this array. This method exists to permit the use in a for-each loop.
      Specified by:
      iterator in interface Iterable<A>
      Returns:
      A iterator for this array.
    • get

      public A get(int index)
      Returns the element at the given index if it exists, fails otherwise.
      Parameters:
      index - The index at which to get the element to return.
      Returns:
      The element at the given index if it exists, fails otherwise.
    • hashCode

      public int hashCode()
      Overrides:
      hashCode in class Object
    • set

      public Unit set(int index, A a)
      Sets the element at the given index to the given value.
      Parameters:
      index - The index at which to set the given value.
      a - The value to set at the given index.
      Returns:
      The unit value.
    • length

      public int length()
      Returns the length of this array.
      Returns:
      The length of this array.
    • immutable

      public Array.ImmutableProjection<A> immutable()
    • isEmpty

      public boolean isEmpty()
      Returns true is this array is empty, false otherwise.
      Returns:
      true is this array is empty, false otherwise.
    • isNotEmpty

      public boolean isNotEmpty()
      Returns false is this array is empty, true otherwise.
      Returns:
      false is this array is empty, true otherwise.
    • array

      public A[] array(Class<A[]> c)
      Returns a copy of the underlying primitive array.
      Parameters:
      c - A class for the returned array.
      Returns:
      A copy of the underlying primitive array.
    • array

      public Object[] array()
      Returns a copy of the underlying primitive array.
      Returns:
      A copy of the underlying primitive array;
    • toOption

      public Option<A> toOption()
      Returns an option projection of this array; None if empty, or the first element in Some.
      Returns:
      An option projection of this array.
    • toEither

      public <X> Either<X,A> toEither(F0<X> x)
      Returns an either projection of this array; the given argument in Left if empty, or the first element in Right.
      Parameters:
      x - The value to return in left if this array is empty.
      Returns:
      An either projection of this array.
    • toList

      public List<A> toList()
      Returns a list projection of this array.
      Returns:
      A list projection of this array.
    • toStream

      public Stream<A> toStream()
      Returns a stream projection of this array.
      Returns:
      A stream projection of this array.
    • toString

      public String toString()
      Overrides:
      toString in class Object
    • map

      public <B> Array<B> map(F<A,B> f)
      Maps the given function across this array.
      Parameters:
      f - The function to map across this array.
      Returns:
      A new array after the given function has been applied to each element.
    • filter

      public Array<A> filter(F<A,Boolean> f)
      Filters elements from this array by returning only elements which produce true when the given function is applied to them.
      Parameters:
      f - The predicate function to filter on.
      Returns:
      A new array whose elements all match the given predicate.
    • foreach

      public Unit foreach(F<A,Unit> f)
      Performs a side-effect for each element of this array.
      Parameters:
      f - The side-effect to perform for the given element.
      Returns:
      The unit value.
    • foreachDoEffect

      public void foreachDoEffect(Effect1<A> f)
      Performs a side-effect for each element of this array.
      Parameters:
      f - The side-effect to perform for the given element.
    • foldRight

      public <B> B foldRight(F<A,F<B,B>> f, B b)
      Performs a right-fold reduction across this array. This function runs in constant stack space.
      Parameters:
      f - The function to apply on each element of the array.
      b - The beginning value to start the application from.
      Returns:
      The final result after the right-fold reduction.
    • foldRight

      public <B> B foldRight(F2<A,B,B> f, B b)
      Performs a right-fold reduction across this array. This function runs in constant stack space.
      Parameters:
      f - The function to apply on each element of the array.
      b - The beginning value to start the application from.
      Returns:
      The final result after the right-fold reduction.
    • foldLeft

      public <B> B foldLeft(F<B,F<A,B>> f, B b)
      Performs a left-fold reduction across this array. This function runs in constant space.
      Parameters:
      f - The function to apply on each element of the array.
      b - The beginning value to start the application from.
      Returns:
      The final result after the left-fold reduction.
    • foldLeft

      public <B> B foldLeft(F2<B,A,B> f, B b)
      Performs a left-fold reduction across this array. This function runs in constant space.
      Parameters:
      f - The function to apply on each element of the array.
      b - The beginning value to start the application from.
      Returns:
      The final result after the left-fold reduction.
    • scanLeft

      public <B> Array<B> scanLeft(F<B,F<A,B>> f, B b)
      Performs a fold left accummulating and returns an array of the intermediate results. This function runs in constant stack space.
      Parameters:
      f - The function to apply on each argument pair (initial value/previous result and next array element)
      b - The beginning value to start the application from.
      Returns:
      The array containing all intermediate results of the left-fold reduction.
    • scanLeft

      public <B> Array<B> scanLeft(F2<B,A,B> f, B b)
      Performs a left-fold accummulating and returns an array of the intermediate results. This function runs in constant stack space.
      Parameters:
      f - The function to apply on each argument pair (initial value/previous result and next array element)
      b - The beginning value to start the application from.
      Returns:
      The array containing all intermediate results of the left-fold reduction.
    • scanLeft1

      public Array<A> scanLeft1(F<A,F<A,A>> f)
      Performs a left-fold accummulating using first array element as a starting value and returns an array of the intermediate results. It will fail for empty arrays. This function runs in constant stack space.
      Parameters:
      f - The function to apply on each argument pair (next array element and first array element/previous result)
      Returns:
      The array containing all intermediate results of the left-fold reduction.
    • scanLeft1

      public Array<A> scanLeft1(F2<A,A,A> f)
      Performs a left-fold accummulating using first array element as a starting value and returns an array of the intermediate results. It will fail for empty arrays. This function runs in constant stack space.
      Parameters:
      f - The function to apply on each argument pair (next array element and first array element/previous result)
      Returns:
      The array containing all intermediate results of the left-fold reduction.
    • scanRight

      public <B> Array<B> scanRight(F<A,F<B,B>> f, B b)
      Performs a right-fold accummulating and returns an array of the intermediate results. This function runs in constant stack space.
      Parameters:
      f - The function to apply on each argument pair (previous array element and initial value/previous result)
      b - The beginning value to start the application from.
      Returns:
      The array containing all intermediate results of the right-fold reduction.
    • scanRight

      public <B> Array<B> scanRight(F2<A,B,B> f, B b)
      Performs a right-fold accummulating and returns an array of the intermediate results. This function runs in constant stack space.
      Parameters:
      f - The function to apply on each argument pair (previous array element and initial value/previous result)
      b - The beginning value to start the application from.
      Returns:
      The array containing all intermediate results of the right-fold reduction.
    • scanRight1

      public Array<A> scanRight1(F<A,F<A,A>> f)
      Performs a right-fold accummulating using last array element as a starting value and returns an array of the intermediate results. It will fail for empty arrays. This function runs in constant stack space.
      Parameters:
      f - The function to apply on each argument pair (previous array element and last array element/previous result)
      Returns:
      The array containing all intermediate results of the right-fold reduction.
    • scanRight1

      public Array<A> scanRight1(F2<A,A,A> f)
      Performs a right-fold accummulating using last array element as a starting value and returns an array of the intermediate results. It will fail for empty arrays. This function runs in constant stack space.
      Parameters:
      f - The function to apply on each argument pair (previous array element and last array element/previous result)
      Returns:
      The array containing all intermediate results of the right-fold reduction.
    • bind

      public <B> Array<B> bind(F<A,Array<B>> f)
      Binds the given function across each element of this array with a final join.
      Parameters:
      f - The function to apply to each element of this array.
      Returns:
      A new array after performing the map, then final join.
    • sequence

      public <B> Array<B> sequence(Array<B> bs)
      Performs a bind across each array element, but ignores the element value each time.
      Parameters:
      bs - The array to apply in the final join.
      Returns:
      A new array after the final join.
    • bind

      public <B, C> Array<C> bind(Array<B> sb, F<A,F<B,C>> f)
      Binds the given function across each element of this array and the given array with a final join.
      Parameters:
      sb - A given array to bind the given function with.
      f - The function to apply to each element of this array and the given array.
      Returns:
      A new array after performing the map, then final join.
    • bind

      public <B, C> Array<C> bind(Array<B> sb, F2<A,B,C> f)
      Binds the given function across each element of this array and the given array with a final join.
      Parameters:
      sb - A given array to bind the given function with.
      f - The function to apply to each element of this array and the given array.
      Returns:
      A new array after performing the map, then final join.
    • apply

      public <B> Array<B> apply(Array<F<A,B>> lf)
      Performs function application within an array (applicative functor pattern).
      Parameters:
      lf - The array of functions to apply.
      Returns:
      A new array after applying the given array of functions through this array.
    • reverse

      public Array<A> reverse()
      Reverse this array in constant stack space.
      Returns:
      A new array that is the reverse of this one.
    • append

      public Array<A> append(Array<A> aas)
      Appends the given array to this array.
      Parameters:
      aas - The array to append to this one.
      Returns:
      A new array that has appended the given array.
    • empty

      public static <A> Array<A> empty()
      Returns an empty array.
      Returns:
      An empty array.
    • array

      @SafeVarargs public static <A> Array<A> array(A... as)
      Constructs an array from the given elements.
      Parameters:
      as - The elements to construct the array with.
      Returns:
      A new array of the given elements.
    • mkArray

      static <A> Array<A> mkArray(Object[] a)
      Unsafe package-private constructor. The elements of the given array must be assignable to the given type.
      Parameters:
      a - An array with elements of the given type.
      Returns:
      A wrapped array.
    • single

      public static <A> Array<A> single(A a)
      Constructs a singleton array.
      Parameters:
      a - The element to put in the array.
      Returns:
      An array with the given single element.
    • wrap

      public static <A> F<A[],Array<A>> wrap()
      First-class wrapper function for arrays.
      Returns:
      A function that wraps a given array.
    • map

      public static <A, B> F<F<A,B>,F<Array<A>,Array<B>>> map()
      First-class map function for Arrays.
      Returns:
      A function that maps a given function across a given array.
    • join

      public static <A> Array<A> join(Array<Array<A>> o)
      Joins the given array of arrays using a bind operation.
      Parameters:
      o - The array of arrays to join.
      Returns:
      A new array that is the join of the given arrays.
    • join

      public static <A> F<Array<Array<A>>,Array<A>> join()
      A first-class version of join
      Returns:
      A function that joins a array of arrays using a bind operation.
    • forall

      public boolean forall(F<A,Boolean> f)
      Returns true if the predicate holds for all of the elements of this array, false otherwise (true for the empty array).
      Parameters:
      f - the predicate function to test on each element of this array.
      Returns:
      true if the predicate holds for all of the elements of this array, false otherwise.
    • exists

      public boolean exists(F<A,Boolean> f)
      Returns true if the predicate holds for at least one of the elements of this array, false otherwise (false for the empty array).
      Parameters:
      f - the predicate function to test on the elements of this array.
      Returns:
      true if the predicate holds for at least one of the elements of this array.
    • equals

      public boolean equals(Object o)
      Overrides:
      equals in class Object
    • find

      public Option<A> find(F<A,Boolean> f)
      Finds the first occurrence of an element that matches the given predicate or no value if no elements match.
      Parameters:
      f - The predicate function to test on elements of this array.
      Returns:
      The first occurrence of an element that matches the given predicate or no value if no elements match.
    • range

      public static Array<Integer> range(int from, int to)
      Returns an array of integers from the given from value (inclusive) to the given to value (exclusive).
      Parameters:
      from - The minimum value for the array (inclusive).
      to - The maximum value for the array (exclusive).
      Returns:
      An array of integers from the given from value (inclusive) to the given to value (exclusive).
    • zipWith

      public <B, C> Array<C> zipWith(Array<B> bs, F<A,F<B,C>> f)
      Zips this array with the given array using the given function to produce a new array. If this array and the given array have different lengths, then the longer array is normalised so this function never fails.
      Parameters:
      bs - The array to zip this array with.
      f - The function to zip this array and the given array with.
      Returns:
      A new array with a length the same as the shortest of this array and the given array.
    • zipWith

      public <B, C> Array<C> zipWith(Array<B> bs, F2<A,B,C> f)
      Zips this array with the given array using the given function to produce a new array. If this array and the given array have different lengths, then the longer array is normalised so this function never fails.
      Parameters:
      bs - The array to zip this array with.
      f - The function to zip this array and the given array with.
      Returns:
      A new array with a length the same as the shortest of this array and the given array.
    • zip

      public <B> Array<P2<A,B>> zip(Array<B> bs)
      Zips this array with the given array to produce an array of pairs. If this array and the given array have different lengths, then the longer array is normalised so this function never fails.
      Parameters:
      bs - The array to zip this array with.
      Returns:
      A new array with a length the same as the shortest of this array and the given array.
    • zipIndex

      public Array<P2<A,Integer>> zipIndex()
      Zips this array with the index of its element as a pair.
      Returns:
      A new array with the same length as this array.
    • toCollection

      public Collection<A> toCollection()
      Projects an immutable collection of this array.
      Returns:
      An immutable collection of this array.
    • asJavaList

      public List<A> asJavaList()
      Projects an unmodifiable list view of this array.
      Returns:
      An unmodifiable list view of this array.
    • toJavaList

      public ArrayList<A> toJavaList()
      Returns a java.util.ArrayList projection of this array.
    • iterableArray

      public static <A> Array<A> iterableArray(Iterable<A> i)
      Takes the given iterable to an array.
      Parameters:
      i - The iterable to take to an array.
      Returns:
      An array from the given iterable.
    • iteratorArray

      public static <A> Array<A> iteratorArray(Iterator<A> i)
      Creates an Array from the iterator.
    • arrayArray

      @SafeVarargs public static <A> Array<A> arrayArray(A... as)
      Returns a copy of the underlying primitive array. Equivalent to array(A...)
      Returns:
      A copy of the underlying primitive array.
    • unzip

      public static <A, B> P2<Array<A>,Array<B>> unzip(Array<P2<A,B>> xs)
      Transforms an array of pairs into an array of first components and an array of second components.
      Parameters:
      xs - The array of pairs to transform.
      Returns:
      An array of first components and an array of second components.
    • copyOf

      public static <T, U> T[] copyOf(U[] a, int len, Class<? extends T[]> newType)
    • copyOf

      public static <T> T[] copyOf(T[] a, int len)
    • copyOfRange

      public static char[] copyOfRange(char[] a, int from, int to)