Interface LongCollection

All Superinterfaces:
Collection<Long>, Iterable<Long>, LongIterable
All Known Subinterfaces:
LongBigList, LongList, LongSet, LongSortedSet
All Known Implementing Classes:
AbstractLongBigList, AbstractLongBigList.LongRandomAccessSubList, AbstractLongBigList.LongSubList, AbstractLongCollection, AbstractLongList, AbstractLongList.LongRandomAccessSubList, AbstractLongList.LongSubList, AbstractLongSet, AbstractLongSortedSet, LongArrayList, LongArraySet, LongAVLTreeSet, LongBigArrayBigList, LongBigLists.EmptyBigList, LongBigLists.ListBigList, LongBigLists.Singleton, LongBigLists.SynchronizedBigList, LongBigLists.UnmodifiableBigList, LongCollections.EmptyCollection, LongCollections.IterableCollection, LongImmutableList, LongLinkedOpenCustomHashSet, LongLinkedOpenHashSet, LongLists.EmptyList, LongLists.Singleton, LongLists.SynchronizedList, LongLists.SynchronizedRandomAccessList, LongLists.UnmodifiableList, LongLists.UnmodifiableRandomAccessList, LongMappedBigList, LongOpenCustomHashSet, LongOpenHashBigSet, LongOpenHashSet, LongRBTreeSet, LongSets.EmptySet, LongSets.Singleton, LongSets.SynchronizedSet, LongSets.UnmodifiableSet, LongSortedSets.EmptySet, LongSortedSets.Singleton, LongSortedSets.SynchronizedSortedSet, LongSortedSets.UnmodifiableSortedSet

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

Additionally, this class defines strengthens (again) iterator().

This interface specifies reference equality semantics (members will be compared equal with == instead of equals), which may result in breaks in contract if attempted to be used with non reference-equality semantics based Collections. For example, a aReferenceCollection.equals(aObjectCollection) may return different a different result then aObjectCollection.equals(aReferenceCollection), in violation of equals's contract requiring it being symmetric.

See Also:
  • Method Summary

    Modifier and Type
    Method
    Description
    boolean
    add(long key)
    Ensures that this collection contains the specified element (optional operation).
    default boolean
    add(Long key)
    Deprecated.
    Please use the corresponding type-specific method instead.
    boolean
    Adds all elements of the given type-specific collection to this collection.
    boolean
    contains(long key)
    Returns true if this collection contains the specified element.
    default boolean
    Deprecated.
    Please use the corresponding type-specific method instead.
    boolean
    Checks whether this collection contains all elements from the given type-specific collection.
    Returns a type-specific iterator on the elements of this collection.
    default LongIterator
    Returns a primitive iterator on the elements of this collection.
    default LongStream
    Return a parallel primitive stream over the elements, performing widening casts if needed.
    Returns a primitive spliterator on the elements of this collection.
    default LongStream
    Return a primitive stream over the elements, performing widening casts if needed.
    default Stream<Long>
    Deprecated.
    Please use the corresponding type-specific method instead.
    boolean
    rem(long key)
    Removes a single instance of the specified element from this collection, if it is present (optional operation).
    default boolean
    Deprecated.
    Please use (and implement) the rem() method instead.
    boolean
    Remove from this collection all elements in the given type-specific collection.
    default boolean
    Remove from this collection all elements which satisfy the given predicate.
    default boolean
    Remove from this collection all elements which satisfy the given predicate.
    default boolean
    removeIf(Predicate<? super Long> filter)
    Deprecated.
    Please use the corresponding type-specific method instead.
    boolean
    Retains in this collection only elements from the given type-specific collection.
    Returns a type-specific spliterator on the elements of this collection.
    default Stream<Long>
    Deprecated.
    Please use the corresponding type-specific method instead.
    long[]
    toArray(long[] a)
    Returns an array containing all of the elements in this collection; the runtime type of the returned array is that of the specified array.
    long[]
    Returns a primitive type array containing the items of this collection.
    default long[]
    toLongArray(long[] a)
    Deprecated.
    Please use toArray() instead—this method is redundant and will be removed in the future.

    Methods inherited from interface java.util.Collection

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

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

    forEach, forEach, forEach
  • Method Details

    • iterator

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

      default LongIterator longIterator()
      Returns a primitive iterator on the elements of this collection.

      This method is identical to iterator(), as the type-specific iterator is already compatible with the JDK's primitive iterators. It only exists for compatibility with the other primitive types' Collections that have use for widened iterators.

      Specified by:
      longIterator in interface LongIterable
      Returns:
      a primitive iterator on the elements of this collection.
      Since:
      8.5.0
    • spliterator

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

      See Collection.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 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().

      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) that wraps this instance's type specific iterator().

      Additionally, it reports Spliterator.SIZED

      Implementation Notes:
      As this default implementation wraps 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.
    • longSpliterator

      default LongSpliterator longSpliterator()
      Returns a primitive spliterator on the elements of this collection.

      This method is identical to spliterator(), as the type-specific spliterator is already compatible with the JDK's primitive spliterators. It only exists for compatibility with the other primitive types' Collections that have use for widened spliterators.

      Specified by:
      longSpliterator in interface LongIterable
      Returns:
      a primitive spliterator on the elements of this collection.
      Since:
      8.5.0
    • add

      boolean add(long key)
      Ensures that this collection contains the specified element (optional operation).
      See Also:
    • contains

      boolean contains(long key)
      Returns true if this collection contains the specified element.
      See Also:
    • rem

      boolean rem(long key)
      Removes a single instance of the specified element from this collection, if it is present (optional operation).

      Note that this method should be called remove(), but the clash with the similarly named index-based method in the List interface forces us to use a distinguished name. For simplicity, the set interfaces reinstates remove().

      See Also:
    • add

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

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

      @Deprecated default boolean remove(Object key)
      Deprecated.
      Please use (and implement) the rem() method instead.
      Specified by:
      remove in interface Collection<Long>
    • toLongArray

      long[] toLongArray()
      Returns a primitive type array containing the items of this collection.
      Returns:
      a primitive type array containing the items of this collection.
      See Also:
    • toLongArray

      @Deprecated default long[] toLongArray(long[] a)
      Deprecated.
      Please use toArray() instead—this method is redundant and will be removed in the future.
      Returns a primitive type array containing the items of this collection.

      Note that, contrarily to Collection.toArray(Object[]), this methods just writes all elements of this collection: no special value will be added after the last one.

      Parameters:
      a - if this array is big enough, it will be used to store this collection.
      Returns:
      a primitive type array containing the items of this collection.
      See Also:
    • toArray

      long[] toArray(long[] a)
      Returns an array containing all of the elements in this collection; the runtime type of the returned array is that of the specified array.

      Note that, contrarily to Collection.toArray(Object[]), this methods just writes all elements of this collection: no special value will be added after the last one.

      Parameters:
      a - if this array is big enough, it will be used to store this collection.
      Returns:
      a primitive type array containing the items of this collection.
      See Also:
    • addAll

      boolean addAll(LongCollection c)
      Adds all elements of the given type-specific collection to this collection.
      Parameters:
      c - a type-specific collection.
      Returns:
      true if this collection changed as a result of the call.
      See Also:
    • containsAll

      boolean containsAll(LongCollection c)
      Checks whether this collection contains all elements from the given type-specific collection.
      Parameters:
      c - a type-specific collection.
      Returns:
      true if this collection contains all elements of the argument.
      See Also:
    • removeAll

      boolean removeAll(LongCollection c)
      Remove from this collection all elements in the given type-specific collection.
      Parameters:
      c - a type-specific collection.
      Returns:
      true if this collection changed as a result of the call.
      See Also:
    • removeIf

      @Deprecated default boolean removeIf(Predicate<? super Long> filter)
      Deprecated.
      Please use the corresponding type-specific method instead.
      Specified by:
      removeIf in interface Collection<Long>
    • removeIf

      default boolean removeIf(LongPredicate filter)
      Remove from this collection all elements which satisfy the given predicate.
      Parameters:
      filter - a predicate which returns true for elements to be removed.
      Returns:
      true if any elements were removed.
      See Also:
      API Notes:
      Implementing classes should generally override this method, and take the default implementation of the other overloads which will delegate to this method (after proper conversions).
    • removeIf

      default boolean removeIf(LongPredicate filter)
      Remove from this collection all elements which satisfy the given predicate.

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

      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.XPredicate, 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:
      filter - a predicate which returns true for elements to be removed.
      Returns:
      true if any elements were removed.
      See Also:
    • retainAll

      boolean retainAll(LongCollection c)
      Retains in this collection only elements from the given type-specific collection.
      Parameters:
      c - a type-specific collection.
      Returns:
      true if this collection changed as a result of the call.
      See Also:
    • stream

      @Deprecated default Stream<Long> stream()
      Deprecated.
      Please use the corresponding type-specific method instead.
      Specified by:
      stream in interface Collection<Long>
    • longStream

      default LongStream longStream()
      Return a primitive stream over the elements, performing widening casts if needed.
      Returns:
      a primitive stream over the elements.
      See Also:
    • parallelStream

      @Deprecated default Stream<Long> parallelStream()
      Deprecated.
      Please use the corresponding type-specific method instead.
      Specified by:
      parallelStream in interface Collection<Long>
    • longParallelStream

      default LongStream longParallelStream()
      Return a parallel primitive stream over the elements, performing widening casts if needed.
      Returns:
      a parallel primitive stream over the elements.
      See Also: