Added in API level 30

Subscriber

interface Subscriber<T : Any!>

java.util.concurrent.Flow.Subscriber

Known Direct Subclasses

Flow.Processor

A component that acts as both a Subscriber and Publisher.

A receiver of messages. The methods in this interface are invoked in strict sequential order for each Subscription.

Summary

Public methods
abstract Unit	`onComplete()` Method invoked when it is known that no additional Subscriber method invocations will occur for a Subscription that is not already terminated by error, after which no other Subscriber methods are invoked by the Subscription.
abstract Unit	`onError(throwable: Throwable!)` Method invoked upon an unrecoverable error encountered by a Publisher or Subscription, after which no other Subscriber methods are invoked by the Subscription.
abstract Unit	`onNext(item: T)` Method invoked with a Subscription's next item.
abstract Unit	`onSubscribe(subscription: Flow.Subscription!)` Method invoked prior to invoking any other Subscriber methods for the given Subscription.

Public methods

onComplete

Added in API level 30

abstract fun onComplete(): Unit

Method invoked when it is known that no additional Subscriber method invocations will occur for a Subscription that is not already terminated by error, after which no other Subscriber methods are invoked by the Subscription. If this method throws an exception, resulting behavior is undefined.

onError

Added in API level 30

abstract fun onError(throwable: Throwable!): Unit

Method invoked upon an unrecoverable error encountered by a Publisher or Subscription, after which no other Subscriber methods are invoked by the Subscription. If this method itself throws an exception, resulting behavior is undefined.

Parameters
`throwable`	Throwable!: the exception

onNext

Added in API level 30

abstract fun onNext(item: T): Unit

Method invoked with a Subscription's next item. If this method throws an exception, resulting behavior is not guaranteed, but may cause the Subscription to be cancelled.

Parameters
`item`	T: the item

onSubscribe

Added in API level 30

abstract fun onSubscribe(subscription: Flow.Subscription!): Unit

Method invoked prior to invoking any other Subscriber methods for the given Subscription. If this method throws an exception, resulting behavior is not guaranteed, but may cause the Subscription not to be established or to be cancelled.

Typically, implementations of this method invoke subscription.request to enable receiving items.

Parameters
`subscription`	Flow.Subscription!: a new subscription