Method Details

• tryInitialize

  public static boolean tryInitialize(com.fasterxml.jackson.databind.ObjectMapper objectMapper, Executor dispatcher)

  Initializes the global signal environment if not already initialized. The provided values are ignored if the environment is already initialized. The environment must be initialized before signals are used.

  Parameters:

  objectMapper - the object mapper to use, not null

  dispatcher - the asynchronous dispatcher to use, not null

  Returns:

  true if the provided values were used to initialize the environment, false if the environment was already initialized

• initialized

  public static boolean initialized()

  Checks whether the environment is already initialized.

  Returns:

  true if initialized, false if not initialized

• addDispatcherOverride

  public static Runnable addDispatcherOverride(Supplier<Executor> dispatcherOverride)

  Adds a new supplier for override dispatchers. A supplier can inspect the circumstances under in which it's run and optionally provide a dispatcher to use for tasks initiated under those circumstances. The supplier is expected to use its own thread local variables to understand the context.

  The dispatcher is used both for asynchronously dispatched effect callbacks and for resolving signal operation results. The dispatcher needs to preserve ordering within the context that it belongs to (which is up to the implementation to define) so that operation results are published in order of confirmation.

  Parameters:

  dispatcherOverride - a supplier that can return a dispatcher to use or null to not provide any dispatcher under those circumstances. Not null.

  Returns:

  a callback that can be used to unregister the supplier, not null

• objectMapper

  public static com.fasterxml.jackson.databind.ObjectMapper objectMapper()

  Gets the object mapper to use for converting signal values to and from their underlying JSON representation

  Returns:

  the object mapper, not null

  Throws:

  IllegalStateException - if the environment has not yet been initialized

• defaultDispatcher

  public static Executor defaultDispatcher()

  Gets the dispatcher that was set when the environment was initialized without looking up overrides.

  Returns:

  the configured dispatcher, not null

  Throws:

  IllegalStateException - if the environment has not yet been initialized

• asynchronousDispatcher

  public static Executor asynchronousDispatcher()

  Gets a dispatcher to use for asynchronous tasks. This is used e.g. for running effect callbacks. The dispatcher does not guarantee that tasks are run in the order they have been submitted. This method uses a dispatcher override if any supplier matches and otherwise uses the dispatcher provided when the environment was initialized.

  Returns:

  the dispatcher to use, not null

  Throws:

  IllegalStateException - if the environment has not yet been initialized

• synchronousDispatcher

  public static Executor synchronousDispatcher()

  Gets a dispatcher to use for synchronous tasks. This is used e.g. for resolving operation results. The dispatcher guarantees that tasks for the same context are run in the order they have been submitted. This method uses a dispatcher override if any supplier matches and otherwise uses a dispatcher that runs tasks on the invoking thread.

  Returns:

  the dispatcher to use, not null

  Throws:

  IllegalStateException - if the environment has not yet been initialized