@NonNullApi @NonNullFields

# Package org.springframework.util.concurrent

Useful generic `java.util.concurrent.Future` extensions.

See: Description

- Interface Summary
  Interface | Description
  --- | ---
  FailureCallback | Failure callback for a `ListenableFuture`.
  ListenableFuture<T> | Extend `Future` with the capability to accept completion callbacks.
  ListenableFutureCallback<T> | Callback mechanism for the outcome, success or failure, from a `ListenableFuture`.
  SuccessCallback<T> | Success callback for a `ListenableFuture`.

- Class Summary
  Class | Description
  --- | ---
  CompletableToListenableFutureAdapter<T> | Adapts a `CompletableFuture` or `CompletionStage` into a Spring `ListenableFuture`.
  FutureAdapter<T,S> | Abstract class that adapts a `Future` parameterized over S into a `Future` parameterized over T.
  ListenableFutureAdapter<T,S> | Abstract class that adapts a `ListenableFuture` parameterized over S into a `ListenableFuture` parameterized over T.
  ListenableFutureCallbackRegistry<T> | Helper class for `ListenableFuture` implementations that maintains a queue of success and failure callbacks and helps to notify them.
  ListenableFutureTask<T> | Extension of `FutureTask` that implements `ListenableFuture`.
  MonoToListenableFutureAdapter<T> | Adapts a `Mono` into a `ListenableFuture` by obtaining a `CompletableFuture` from the `Mono` via `Mono.toFuture()` and then adapting it with `CompletableToListenableFutureAdapter`.
  SettableListenableFuture<T> | A `ListenableFuture` whose value can be set via `SettableListenableFuture.set(Object)` or `SettableListenableFuture.setException(Throwable)`.

## Package org.springframework.util.concurrent Description

Useful generic `java.util.concurrent.Future` extensions.