Module java.base

Enum Collector.Characteristics

All Implemented Interfaces:
Serializable, Comparable<Collector.Characteristics>, Constable
Enclosing interface:

public static enum Collector.Characteristics
extends Enum<Collector.Characteristics>
Characteristics indicating properties of a Collector, which can be used to optimize reduction implementations.
  • Enum Constant Details


      public static final Collector.Characteristics CONCURRENT
      Indicates that this collector is concurrent, meaning that the result container can support the accumulator function being called concurrently with the same result container from multiple threads.

      If a CONCURRENT collector is not also UNORDERED, then it should only be evaluated concurrently if applied to an unordered data source.


      public static final Collector.Characteristics UNORDERED
      Indicates that the collection operation does not commit to preserving the encounter order of input elements. (This might be true if the result container has no intrinsic order, such as a Set.)

      public static final Collector.Characteristics IDENTITY_FINISH
      Indicates that the finisher function is the identity function and can be elided. If set, it must be the case that an unchecked cast from A to R will succeed.
  • Method Details

    • values

      public static Collector.Characteristics[] values()
      Returns an array containing the constants of this enum type, in the order they are declared.
      an array containing the constants of this enum type, in the order they are declared
    • valueOf

      public static Collector.Characteristics valueOf​(String name)
      Returns the enum constant of this type with the specified name. The string must match exactly an identifier used to declare an enum constant in this type. (Extraneous whitespace characters are not permitted.)
      name - the name of the enum constant to be returned.
      the enum constant with the specified name
      IllegalArgumentException - if this enum type has no constant with the specified name
      NullPointerException - if the argument is null