Package org.incendo.cloud.state

Interface Stateful<S extends State>

Type Parameters:
S - the state type
All Known Implementing Classes:
CommandManager
@API(status=STABLE) public interface Stateful<S extends State>
A simple state machine.

  • Method Summary

    Modifier and Type
    Method
    Description
    default void
    requireState(@NonNull S expected)
    Requires that the current state() is equal to the expected state, and fails exceptionally if the states are different.
    @NonNull S
    state()
    Returns the current state.
    boolean
    transitionIfPossible(@NonNull S in, @NonNull S out)
    Transitions from the in state to the out state, unless the current state() is identical to the out state.
    default void
    transitionOrThrow(@NonNull S in, @NonNull S out)
    Transitions from the in state to the out state, unless the current state() is identical to the out state.

  • Method Details

    • state

      @NonNull S state()
      Returns the current state.
      Returns:
      the current state

    • transitionIfPossible

      boolean transitionIfPossible(@NonNull S in, @NonNull S out)
      Transitions from the in state to the out state, unless the current state() is identical to the out state.
      Parameters:
      in - the starting state
      out - the ending state
      Returns:
      true if the state transition was successful, or the current state is identical to the out state

    • requireState

      default void requireState(@NonNull S expected)
      Requires that the current state() is equal to the expected state, and fails exceptionally if the states are different.
      Parameters:
      expected - the expected state
      Throws:
      IllegalStateException - if the current state() is different from the expected state

    • transitionOrThrow

      default void transitionOrThrow(@NonNull S in, @NonNull S out)
      Transitions from the in state to the out state, unless the current state() is identical to the out state.
      Parameters:
      in - the starting state
      out - the ending state
      Throws:
      IllegalStateException - if state transition is not possible