Class StreamSupport

java.lang.Object
java.util.stream.StreamSupport
public final class StreamSupport extends Object
Low-level utility methods for creating and manipulating streams.

This class is mostly for library writers presenting stream views of data structures; most static stream methods intended for end users are in the various Stream classes.

Since:
1.8

  • Method Summary

    Modifier and Type
    Method
    Description
    static DoubleStream
    doubleStream(Supplier<? extends Spliterator.OfDouble> supplier, int characteristics, boolean parallel)
    Creates a new sequential or parallel DoubleStream from a Supplier of Spliterator.OfDouble.
    static DoubleStream
    doubleStream(Spliterator.OfDouble spliterator, boolean parallel)
    Creates a new sequential or parallel DoubleStream from a Spliterator.OfDouble.
    static IntStream
    intStream(Supplier<? extends Spliterator.OfInt> supplier, int characteristics, boolean parallel)
    Creates a new sequential or parallel IntStream from a Supplier of Spliterator.OfInt.
    static IntStream
    intStream(Spliterator.OfInt spliterator, boolean parallel)
    Creates a new sequential or parallel IntStream from a Spliterator.OfInt.
    static LongStream
    longStream(Supplier<? extends Spliterator.OfLong> supplier, int characteristics, boolean parallel)
    Creates a new sequential or parallel LongStream from a Supplier of Spliterator.OfLong.
    static LongStream
    longStream(Spliterator.OfLong spliterator, boolean parallel)
    Creates a new sequential or parallel LongStream from a Spliterator.OfLong.
    static <T> Stream<T>
    stream(Supplier<? extends Spliterator<T>> supplier, int characteristics, boolean parallel)
    Creates a new sequential or parallel Stream from a Supplier of Spliterator.
    static <T> Stream<T>
    stream(Spliterator<T> spliterator, boolean parallel)
    Creates a new sequential or parallel Stream from a Spliterator.

    Methods declared in class Object

    clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait
    Modifier and Type
    Method
    Description
    protected Object
    clone()
    Answers a new instance of the same class as the receiver, whose slots have been filled in with the values in the slots of the receiver.
    boolean
    equals(Object o)
    Compares the argument to the receiver, and answers true if they represent the same object using a class specific comparison.
    protected void
    finalize()
    Deprecated, for removal: This API element is subject to removal in a future version.
    May cause performance issues, deadlocks and hangs.
    final Class<? extends Object>
    getClass()
    Answers the unique instance of java.lang.Class which represents the class of the receiver.
    int
    hashCode()
    Answers an integer hash code for the receiver.
    final void
    notify()
    Causes one thread which is waiting on the receiver to be made ready to run.
    final void
    notifyAll()
    Causes all threads which are waiting on the receiver to be made ready to run.
    String
    toString()
    Answers a string containing a concise, human-readable description of the receiver.
    final void
    wait()
    Causes the thread which sent this message to be made not ready to run pending some change in the receiver (as indicated by notify or notifyAll).
    final void
    wait(long time)
    Causes the thread which sent this message to be made not ready to run either pending some change in the receiver (as indicated by notify or notifyAll) or the expiration of the timeout.
    final void
    wait(long time, int frac)
    Causes the thread which sent this message to be made not ready to run either pending some change in the receiver (as indicated by notify or notifyAll) or the expiration of the timeout.

  • Method Details

    • stream

      public static <T> Stream<T> stream(Spliterator<T> spliterator, boolean parallel)
      Creates a new sequential or parallel Stream from a Spliterator.

      The spliterator is only traversed, split, or queried for estimated size after the terminal operation of the stream pipeline commences.

      It is strongly recommended the spliterator report a characteristic of IMMUTABLE or CONCURRENT, or be late-binding. Otherwise, stream(java.util.function.Supplier, int, boolean) should be used to reduce the scope of potential interference with the source. See Non-Interference for more details.

      Type Parameters:
      T - the type of stream elements
      Parameters:
      spliterator - a Spliterator describing the stream elements
      parallel - if true then the returned stream is a parallel stream; if false the returned stream is a sequential stream.
      Returns:
      a new sequential or parallel Stream

    • stream

      public static <T> Stream<T> stream(Supplier<? extends Spliterator<T>> supplier, int characteristics, boolean parallel)
      Creates a new sequential or parallel Stream from a Supplier of Spliterator.

      The Supplier.get() method will be invoked on the supplier no more than once, and only after the terminal operation of the stream pipeline commences.

      For spliterators that report a characteristic of IMMUTABLE or CONCURRENT, or that are late-binding, it is likely more efficient to use stream(java.util.Spliterator, boolean) instead.

      The use of a Supplier in this form provides a level of indirection that reduces the scope of potential interference with the source. Since the supplier is only invoked after the terminal operation commences, any modifications to the source up to the start of the terminal operation are reflected in the stream result. See Non-Interference for more details.

      Type Parameters:
      T - the type of stream elements
      Parameters:
      supplier - a Supplier of a Spliterator
      characteristics - Spliterator characteristics of the supplied Spliterator. The characteristics must be equal to supplier.get().characteristics(), otherwise undefined behavior may occur when terminal operation commences.
      parallel - if true then the returned stream is a parallel stream; if false the returned stream is a sequential stream.
      Returns:
      a new sequential or parallel Stream
      See Also:

    • intStream

      public static IntStream intStream(Spliterator.OfInt spliterator, boolean parallel)
      Creates a new sequential or parallel IntStream from a Spliterator.OfInt.

      The spliterator is only traversed, split, or queried for estimated size after the terminal operation of the stream pipeline commences.

      It is strongly recommended the spliterator report a characteristic of IMMUTABLE or CONCURRENT, or be late-binding. Otherwise, intStream(java.util.function.Supplier, int, boolean) should be used to reduce the scope of potential interference with the source. See Non-Interference for more details.

      Parameters:
      spliterator - a Spliterator.OfInt describing the stream elements
      parallel - if true then the returned stream is a parallel stream; if false the returned stream is a sequential stream.
      Returns:
      a new sequential or parallel IntStream

    • intStream

      public static IntStream intStream(Supplier<? extends Spliterator.OfInt> supplier, int characteristics, boolean parallel)
      Creates a new sequential or parallel IntStream from a Supplier of Spliterator.OfInt.

      The Supplier.get() method will be invoked on the supplier no more than once, and only after the terminal operation of the stream pipeline commences.

      For spliterators that report a characteristic of IMMUTABLE or CONCURRENT, or that are late-binding, it is likely more efficient to use intStream(java.util.Spliterator.OfInt, boolean) instead.

      The use of a Supplier in this form provides a level of indirection that reduces the scope of potential interference with the source. Since the supplier is only invoked after the terminal operation commences, any modifications to the source up to the start of the terminal operation are reflected in the stream result. See Non-Interference for more details.

      Parameters:
      supplier - a Supplier of a Spliterator.OfInt
      characteristics - Spliterator characteristics of the supplied Spliterator.OfInt. The characteristics must be equal to supplier.get().characteristics(), otherwise undefined behavior may occur when terminal operation commences.
      parallel - if true then the returned stream is a parallel stream; if false the returned stream is a sequential stream.
      Returns:
      a new sequential or parallel IntStream
      See Also:

    • longStream

      public static LongStream longStream(Spliterator.OfLong spliterator, boolean parallel)
      Creates a new sequential or parallel LongStream from a Spliterator.OfLong.

      The spliterator is only traversed, split, or queried for estimated size after the terminal operation of the stream pipeline commences.

      It is strongly recommended the spliterator report a characteristic of IMMUTABLE or CONCURRENT, or be late-binding. Otherwise, longStream(java.util.function.Supplier, int, boolean) should be used to reduce the scope of potential interference with the source. See Non-Interference for more details.

      Parameters:
      spliterator - a Spliterator.OfLong describing the stream elements
      parallel - if true then the returned stream is a parallel stream; if false the returned stream is a sequential stream.
      Returns:
      a new sequential or parallel LongStream

    • longStream

      public static LongStream longStream(Supplier<? extends Spliterator.OfLong> supplier, int characteristics, boolean parallel)
      Creates a new sequential or parallel LongStream from a Supplier of Spliterator.OfLong.

      The Supplier.get() method will be invoked on the supplier no more than once, and only after the terminal operation of the stream pipeline commences.

      For spliterators that report a characteristic of IMMUTABLE or CONCURRENT, or that are late-binding, it is likely more efficient to use longStream(java.util.Spliterator.OfLong, boolean) instead.

      The use of a Supplier in this form provides a level of indirection that reduces the scope of potential interference with the source. Since the supplier is only invoked after the terminal operation commences, any modifications to the source up to the start of the terminal operation are reflected in the stream result. See Non-Interference for more details.

      Parameters:
      supplier - a Supplier of a Spliterator.OfLong
      characteristics - Spliterator characteristics of the supplied Spliterator.OfLong. The characteristics must be equal to supplier.get().characteristics(), otherwise undefined behavior may occur when terminal operation commences.
      parallel - if true then the returned stream is a parallel stream; if false the returned stream is a sequential stream.
      Returns:
      a new sequential or parallel LongStream
      See Also:

    • doubleStream

      public static DoubleStream doubleStream(Spliterator.OfDouble spliterator, boolean parallel)
      Creates a new sequential or parallel DoubleStream from a Spliterator.OfDouble.

      The spliterator is only traversed, split, or queried for estimated size after the terminal operation of the stream pipeline commences.

      It is strongly recommended the spliterator report a characteristic of IMMUTABLE or CONCURRENT, or be late-binding. Otherwise, doubleStream(java.util.function.Supplier, int, boolean) should be used to reduce the scope of potential interference with the source. See Non-Interference for more details.

      Parameters:
      spliterator - A Spliterator.OfDouble describing the stream elements
      parallel - if true then the returned stream is a parallel stream; if false the returned stream is a sequential stream.
      Returns:
      a new sequential or parallel DoubleStream

    • doubleStream

      public static DoubleStream doubleStream(Supplier<? extends Spliterator.OfDouble> supplier, int characteristics, boolean parallel)
      Creates a new sequential or parallel DoubleStream from a Supplier of Spliterator.OfDouble.

      The Supplier.get() method will be invoked on the supplier no more than once, and only after the terminal operation of the stream pipeline commences.

      For spliterators that report a characteristic of IMMUTABLE or CONCURRENT, or that are late-binding, it is likely more efficient to use doubleStream(java.util.Spliterator.OfDouble, boolean) instead.

      The use of a Supplier in this form provides a level of indirection that reduces the scope of potential interference with the source. Since the supplier is only invoked after the terminal operation commences, any modifications to the source up to the start of the terminal operation are reflected in the stream result. See Non-Interference for more details.

      Parameters:
      supplier - A Supplier of a Spliterator.OfDouble
      characteristics - Spliterator characteristics of the supplied Spliterator.OfDouble. The characteristics must be equal to supplier.get().characteristics(), otherwise undefined behavior may occur when terminal operation commences.
      parallel - if true then the returned stream is a parallel stream; if false the returned stream is a sequential stream.
      Returns:
      a new sequential or parallel DoubleStream
      See Also: