Added in API level 24

Characteristics

class Characteristics
kotlin.Any
   ↳ kotlin.Enum<java.util.stream.Collector.Characteristics>
   ↳ java.util.stream.Collector.Characteristics

Characteristics indicating properties of a Collector, which can be used to optimize reduction implementations.

Summary

Enum values

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.

Indicates that the finisher function is the identity function and can be elided.

Indicates that the collection operation does not commit to preserving the encounter order of input elements.

Enum values

CONCURRENT

Added in API level 24
enum val CONCURRENT : Collector.Characteristics

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.

IDENTITY_FINISH

Added in API level 24
enum val IDENTITY_FINISH : Collector.Characteristics

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.

UNORDERED

Added in API level 24
enum val UNORDERED : Collector.Characteristics

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.)