Interface LongList

All Superinterfaces:
Collection<Long>, Comparable<List<? extends Long>>, Iterable<Long>, List<Long>, LongCollection, LongIterable
All Known Implementing Classes:
AbstractLongList, AbstractLongList.LongRandomAccessSubList, AbstractLongList.LongSubList, LongArrayList, LongImmutableList, LongLists.EmptyList, LongLists.Singleton, LongLists.SynchronizedList, LongLists.SynchronizedRandomAccessList, LongLists.UnmodifiableList, LongLists.UnmodifiableRandomAccessList

public interface LongList extends List<Long>, Comparable<List<? extends Long>>, LongCollection
A type-specific List; provides some additional methods that use polymorphism to avoid (un)boxing.

Note that this type-specific interface extends Comparable: it is expected that implementing classes perform a lexicographical comparison using the standard operator "less then" for primitive types, and the usual compareTo() method for objects.

Additionally, this interface strengthens iterator(), listIterator(), listIterator(int) and subList(int,int). The former had been already strengthened upstream, but unfortunately List re-specifies it.

Besides polymorphic methods, this interfaces specifies methods to copy into an array or remove contiguous sublists. Although the abstract implementation of this interface provides simple, one-by-one implementations of these methods, it is expected that concrete implementation override them with optimized versions.

See Also:
  • Method Summary

    Modifier and Type
    Method
    Description
    void
    add(int index, long key)
    Inserts the specified element at the specified position in this list (optional operation).
    default void
    add(int index, Long key)
    Deprecated.
    Please use the corresponding type-specific method instead.
    boolean
    add(long key)
    Appends the specified element to the end of this list (optional operation).
    default boolean
    add(Long k)
    Deprecated.
    Please use the corresponding type-specific method instead.
    boolean
    addAll(int index, LongCollection c)
    Inserts all of the elements in the specified type-specific collection into this type-specific list at the specified position (optional operation).
    default boolean
    addAll(int index, LongList l)
    Inserts all of the elements in the specified type-specific list into this type-specific list at the specified position (optional operation).
    default boolean
    Appends all of the elements in the specified type-specific list to the end of this type-specific list (optional operation).
    void
    addElements(int index, long[] a)
    Add (hopefully quickly) elements to this type-specific list.
    void
    addElements(int index, long[] a, int offset, int length)
    Add (hopefully quickly) elements to this type-specific list.
    default boolean
    Deprecated.
    Please use the corresponding type-specific method instead.
    default Long
    get(int index)
    Deprecated.
    Please use the corresponding type-specific method instead.
    void
    getElements(int from, long[] a, int offset, int length)
    Copies (hopefully quickly) elements of this type-specific list into the given array.
    long
    getLong(int index)
    Returns the element at the specified position in this list.
    int
    indexOf(long k)
    Returns the index of the first occurrence of the specified element in this list, or -1 if this list does not contain the element.
    default int
    Deprecated.
    Please use the corresponding type-specific method instead.
    Returns a type-specific iterator on the elements of this list.
    int
    lastIndexOf(long k)
    Returns the index of the last occurrence of the specified element in this list, or -1 if this list does not contain the element.
    default int
    Deprecated.
    Please use the corresponding type-specific method instead.
    Returns a type-specific list iterator on the list.
    listIterator(int index)
    Returns a type-specific list iterator on the list starting at a given index.
    static LongList
    of()
    Returns an immutable empty list.
    static LongList
    of(long e)
    Returns an immutable list with the element given.
    static LongList
    of(long... a)
    Returns an immutable list with the elements given.
    static LongList
    of(long e0, long e1)
    Returns an immutable list with the elements given.
    static LongList
    of(long e0, long e1, long e2)
    Returns an immutable list with the elements given.
    default Long
    remove(int index)
    Deprecated.
    Please use the corresponding type-specific method instead.
    default boolean
    Deprecated.
    Please use the corresponding type-specific method instead.
    void
    removeElements(int from, int to)
    Removes (hopefully quickly) elements of this type-specific list.
    long
    removeLong(int index)
    Removes the element at the specified position in this list (optional operation).
    default void
    Replaces each element of this list with the result of applying the operator to that element.
    default void
    Replaces each element of this list with the result of applying the operator to that element.
    default void
    Deprecated.
    Please use the corresponding type-specific method instead.
    long
    set(int index, long k)
    Replaces the element at the specified position in this list with the specified element (optional operation).
    default Long
    set(int index, Long k)
    Deprecated.
    Please use the corresponding type-specific method instead.
    default void
    setElements(int index, long[] a)
    Set (hopefully quickly) elements to match the array given.
    default void
    setElements(int index, long[] a, int offset, int length)
    Set (hopefully quickly) elements to match the array given.
    default void
    setElements(long[] a)
    Set (hopefully quickly) elements to match the array given.
    void
    size(int size)
    Sets the size of this list.
    default void
    sort(LongComparator comparator)
    Sort a list using a type-specific comparator.
    default void
    sort(Comparator<? super Long> comparator)
    Deprecated.
    Please use the corresponding type-specific method instead.
    Returns a type-specific spliterator on the elements of this list.
    subList(int from, int to)
    Returns a type-specific view of the portion of this list from the index from, inclusive, to the index to, exclusive.
    default void
    Sorts this list using a sort not assured to be stable.
    default void
    unstableSort(Comparator<? super Long> comparator)
    Deprecated.
    Please use the corresponding type-specific method instead.

    Methods inherited from interface java.util.Collection

    toArray

    Methods inherited from interface java.lang.Comparable

    compareTo

    Methods inherited from interface java.util.List

    addAll, addAll, clear, containsAll, equals, hashCode, isEmpty, removeAll, retainAll, size, toArray, toArray

    Methods inherited from interface it.unimi.dsi.fastutil.longs.LongIterable

    forEach, forEach, forEach
  • Method Details

    • iterator

      LongListIterator iterator()
      Returns a type-specific iterator on the elements of this list.
      Specified by:
      iterator in interface Collection<Long>
      Specified by:
      iterator in interface Iterable<Long>
      Specified by:
      iterator in interface List<Long>
      Specified by:
      iterator in interface LongCollection
      Specified by:
      iterator in interface LongIterable
      Returns:
      an iterator on the elements of this list.
      See Also:
      API Notes:
      This specification strengthens the one given in List.iterator(). It would not be normally necessary, but Iterable.iterator() is bizarrily re-specified in List.

      Also, this is generally the only iterator method subclasses should override.

    • spliterator

      default LongSpliterator spliterator()
      Returns a type-specific spliterator on the elements of this list.

      List spliterators must report at least Spliterator.SIZED and Spliterator.ORDERED.

      See List.spliterator() for more documentation on the requirements of the returned spliterator.

      Specified by:
      spliterator in interface Collection<Long>
      Specified by:
      spliterator in interface Iterable<Long>
      Specified by:
      spliterator in interface List<Long>
      Specified by:
      spliterator in interface LongCollection
      Specified by:
      spliterator in interface LongIterable
      Returns:
      a type-specific spliterator on the elements of this collection.
      Since:
      8.5.0
      API Notes:
      This specification strengthens the one given in Collection.spliterator(), which was already strengthened in the corresponding type-specific class, but was weakened by the fact that this interface extends List.

      Also, this is generally the only spliterator method subclasses should override.

      Implementation Specification:
      The default implementation returns a late-binding spliterator (see Spliterator for documentation on what binding policies mean).
      • For RandomAccess lists, this will return a spliterator that calls the type-specific get(int) method on the appropriate indexes.
      • Otherwise, the spliterator returned will wrap this instance's type specific iterator().

      In either case, the spliterator reports Spliterator.SIZED, Spliterator.SUBSIZED, and Spliterator.ORDERED.

      Implementation Notes:
      As the non-RandomAccess case is based on the iterator, and Iterator is an inherently linear API, the returned spliterator will yield limited performance gains when run in parallel contexts, as the returned spliterator's trySplit() will have linear runtime.

      For RandomAccess lists, the parallel performance should be reasonable assuming get(int) is truly constant time like RandomAccess suggests.

    • listIterator

      LongListIterator listIterator()
      Returns a type-specific list iterator on the list.
      Specified by:
      listIterator in interface List<Long>
      See Also:
    • listIterator

      LongListIterator listIterator(int index)
      Returns a type-specific list iterator on the list starting at a given index.
      Specified by:
      listIterator in interface List<Long>
      See Also:
    • subList

      LongList subList(int from, int to)
      Returns a type-specific view of the portion of this list from the index from, inclusive, to the index to, exclusive.
      Specified by:
      subList in interface List<Long>
      See Also:
      API Notes:
      This specification strengthens the one given in List.subList(int,int).
    • size

      void size(int size)
      Sets the size of this list.

      If the specified size is smaller than the current size, the last elements are discarded. Otherwise, they are filled with 0/null/false.

      Parameters:
      size - the new size.
    • getElements

      void getElements(int from, long[] a, int offset, int length)
      Copies (hopefully quickly) elements of this type-specific list into the given array.
      Parameters:
      from - the start index (inclusive).
      a - the destination array.
      offset - the offset into the destination array where to store the first element copied.
      length - the number of elements to be copied.
    • removeElements

      void removeElements(int from, int to)
      Removes (hopefully quickly) elements of this type-specific list.
      Parameters:
      from - the start index (inclusive).
      to - the end index (exclusive).
    • addElements

      void addElements(int index, long[] a)
      Add (hopefully quickly) elements to this type-specific list.
      Parameters:
      index - the index at which to add elements.
      a - the array containing the elements.
    • addElements

      void addElements(int index, long[] a, int offset, int length)
      Add (hopefully quickly) elements to this type-specific list.
      Parameters:
      index - the index at which to add elements.
      a - the array containing the elements.
      offset - the offset of the first element to add.
      length - the number of elements to add.
    • setElements

      default void setElements(long[] a)
      Set (hopefully quickly) elements to match the array given.
      Parameters:
      a - the array containing the elements.
      Since:
      8.3.0
    • setElements

      default void setElements(int index, long[] a)
      Set (hopefully quickly) elements to match the array given.
      Parameters:
      index - the index at which to start setting elements.
      a - the array containing the elements.
      Since:
      8.3.0
    • setElements

      default void setElements(int index, long[] a, int offset, int length)
      Set (hopefully quickly) elements to match the array given. Sets each in this list to the corresponding elements in the array, as if by
       ListIterator iter = listIterator(index);
       int i = 0;
       while (i < length) {
              iter.next();
              iter.set(a[offset + i++]);
       }
       
      However, the exact implementation may be more efficient, taking into account whether random access is faster or not, or at the discretion of subclasses, abuse internals.
      Parameters:
      index - the index at which to start setting elements.
      a - the array containing the elements
      offset - the offset of the first element to add.
      length - the number of elements to add.
      Since:
      8.3.0
    • add

      boolean add(long key)
      Appends the specified element to the end of this list (optional operation).
      Specified by:
      add in interface LongCollection
      See Also:
    • add

      void add(int index, long key)
      Inserts the specified element at the specified position in this list (optional operation).
      See Also:
    • add

      @Deprecated default void add(int index, Long key)
      Deprecated.
      Please use the corresponding type-specific method instead.
      Specified by:
      add in interface List<Long>
    • addAll

      boolean addAll(int index, LongCollection c)
      Inserts all of the elements in the specified type-specific collection into this type-specific list at the specified position (optional operation).
      See Also:
    • set

      long set(int index, long k)
      Replaces the element at the specified position in this list with the specified element (optional operation).
      See Also:
    • replaceAll

      default void replaceAll(LongUnaryOperator operator)
      Replaces each element of this list with the result of applying the operator to that element.
      Parameters:
      operator - the operator to apply to each element.
      See Also:
    • replaceAll

      default void replaceAll(LongUnaryOperator operator)
      Replaces each element of this list with the result of applying the operator to that element.

      WARNING: Overriding this method is almost always a mistake, as this overload only exists to disambiguate. Instead, override the replaceAll() overload that uses the JDK's primitive unary operator type (e.g. IntUnaryOperator).

      If Java supported final default methods, this would be one, but sadly it does not.

      If you checked and are overriding the version with java.util.function.XUnaryOperator, and still see this warning, then your IDE is incorrectly conflating this method with the proper method to override, and you can safely ignore this message.

      Parameters:
      operator - the operator to apply to each element
      Since:
      8.5.0
      See Also:
    • replaceAll

      @Deprecated default void replaceAll(UnaryOperator<Long> operator)
      Deprecated.
      Please use the corresponding type-specific method instead.
      Specified by:
      replaceAll in interface List<Long>
    • getLong

      long getLong(int index)
      Returns the element at the specified position in this list.
      See Also:
    • indexOf

      int indexOf(long k)
      Returns the index of the first occurrence of the specified element in this list, or -1 if this list does not contain the element.
      See Also:
    • lastIndexOf

      int lastIndexOf(long k)
      Returns the index of the last occurrence of the specified element in this list, or -1 if this list does not contain the element.
      See Also:
    • contains

      @Deprecated default boolean contains(Object key)
      Deprecated.
      Please use the corresponding type-specific method instead.
      Specified by:
      contains in interface Collection<Long>
      Specified by:
      contains in interface List<Long>
      Specified by:
      contains in interface LongCollection
    • get

      @Deprecated default Long get(int index)
      Deprecated.
      Please use the corresponding type-specific method instead.
      Specified by:
      get in interface List<Long>
    • indexOf

      @Deprecated default int indexOf(Object o)
      Deprecated.
      Please use the corresponding type-specific method instead.
      Specified by:
      indexOf in interface List<Long>
    • lastIndexOf

      @Deprecated default int lastIndexOf(Object o)
      Deprecated.
      Please use the corresponding type-specific method instead.
      Specified by:
      lastIndexOf in interface List<Long>
    • add

      @Deprecated default boolean add(Long k)
      Deprecated.
      Please use the corresponding type-specific method instead.

      This method specification is a workaround for bug 8177440.

      Specified by:
      add in interface Collection<Long>
      Specified by:
      add in interface List<Long>
      Specified by:
      add in interface LongCollection
    • removeLong

      long removeLong(int index)
      Removes the element at the specified position in this list (optional operation).
      See Also:
    • remove

      @Deprecated default boolean remove(Object key)
      Deprecated.
      Please use the corresponding type-specific method instead.
      Specified by:
      remove in interface Collection<Long>
      Specified by:
      remove in interface List<Long>
      Specified by:
      remove in interface LongCollection
    • remove

      @Deprecated default Long remove(int index)
      Deprecated.
      Please use the corresponding type-specific method instead.
      Specified by:
      remove in interface List<Long>
    • set

      @Deprecated default Long set(int index, Long k)
      Deprecated.
      Please use the corresponding type-specific method instead.
      Specified by:
      set in interface List<Long>
    • addAll

      default boolean addAll(int index, LongList l)
      Inserts all of the elements in the specified type-specific list into this type-specific list at the specified position (optional operation).
      See Also:
      API Notes:
      This method exists only for the sake of efficiency: override are expected to use getElements(int, long[], int, int)/addElements(int, long[]).
      Implementation Specification:
      This method delegates to the one accepting a collection, but it might be implemented more efficiently.
    • addAll

      default boolean addAll(LongList l)
      Appends all of the elements in the specified type-specific list to the end of this type-specific list (optional operation).
      See Also:
      Implementation Specification:
      This method delegates to the index-based version, passing List.size() as first argument.
    • of

      static LongList of()
      Returns an immutable empty list.
      Returns:
      an immutable empty list.
    • of

      static LongList of(long e)
      Returns an immutable list with the element given.
      Parameters:
      e - the element that the returned list will contain.
      Returns:
      an immutable list containing e.
    • of

      static LongList of(long e0, long e1)
      Returns an immutable list with the elements given.
      Parameters:
      e0 - the first element.
      e1 - the second element.
      Returns:
      an immutable list containing e0 and e1.
    • of

      static LongList of(long e0, long e1, long e2)
      Returns an immutable list with the elements given.
      Parameters:
      e0 - the first element.
      e1 - the second element.
      e2 - the third element.
      Returns:
      an immutable list containing e0, e1, and e2.
    • of

      static LongList of(long... a)
      Returns an immutable list with the elements given.

      Note that this method does not perform a defensive copy.

      Parameters:
      a - a list of elements that will be used to initialize the immutable list.
      Returns:
      an immutable list containing the elements of a.
    • sort

      @Deprecated default void sort(Comparator<? super Long> comparator)
      Deprecated.
      Please use the corresponding type-specific method instead.
      Specified by:
      sort in interface List<Long>
    • sort

      default void sort(LongComparator comparator)
      Sort a list using a type-specific comparator.

      Pass null to sort using natural ordering.

      Since:
      8.3.0
      See Also:
      Implementation Specification:
      The default implementation dumps the elements into an array using List.toArray(), sorts the array, then replaces all elements using the setElements(long[]) function.

      It is possible for this method to call unstableSort(java.util.Comparator<? super java.lang.Long>) if it can determine that the results of a stable and unstable sort are completely equivalent. This means if you override unstableSort(java.util.Comparator<? super java.lang.Long>), it should not call this method unless you override this method as well.

    • unstableSort

      @Deprecated default void unstableSort(Comparator<? super Long> comparator)
      Deprecated.
      Please use the corresponding type-specific method instead.
      Sorts this list using a sort not assured to be stable.
    • unstableSort

      default void unstableSort(LongComparator comparator)
      Sorts this list using a sort not assured to be stable.

      Pass null to sort using natural ordering.

      This differs from List.sort(java.util.Comparator) in that the results are not assured to be stable, but may be a bit faster.

      Unless a subclass specifies otherwise, the results of the method if the list is concurrently modified during the sort are unspecified.

      Since:
      8.3.0
      Implementation Specification:
      The default implementation dumps the elements into an array using List.toArray(), sorts the array, then replaces all elements using the setElements(long[]) function.