Class StateMachine<S>

java.lang.Object
nl.colorize.multimedialib.scene.StateMachine<S>
Type Parameters:
S - The type of state represented by this finite state machine. States are considered equal if stateA.equals(stateB). If the state implements the Updatable interface, the update method of the currently active state will be called when the state machine itself receives frame updates.
All Implemented Interfaces:
Updatable
public class StateMachine<S> extends Object implements Updatable
Finite state machine that allows a number of possible states, but can only have one currently active state at any point in time.

The state machine implements the Updatable interface, so it needs to receive frame updates in order to function. Requested states are stored in a queue, with the actual state change only occurring during the frame update.

By default, every state is allowed to transition into every other state. The state machine can optionally be configured to restrict allowed transitions based on the currently active state.

  • Constructor Summary

    Constructors
    Constructor
    Description
    StateMachine(S defaultState)
     

  • Method Summary

    Modifier and Type
    Method
    Description
    void
    forceState(S nextState)
    Forces this state machine into the specified state, clearing the queue so that the requested state becomes active during the next frame update.
    S
    getActiveState()
     
    Timer
    getActiveStateTimer()
     
    boolean
    requestState(S nextState)
    Requests the state machine to transition into the specified state at the earliest opportunity.
    boolean
    requestState(S nextState, float duration)
    Requests the state machine to transition into the specified state at the earliest opportunity.
    void
    update(float deltaTime)
    Updates this state machine based on the elapsed relative time, as specified by the Updatable interface.

    Methods inherited from class Object

    clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

  • Constructor Details

    • StateMachine

      public StateMachine(S defaultState)

  • Method Details

    • requestState

      public boolean requestState(S nextState)
      Requests the state machine to transition into the specified state at the earliest opportunity. Once active, the state will remain active until another state is requested.

      Returns a boolean indicating if the state machine allows a transition from the preceding state in the queue into the requested state.

    • requestState

      public boolean requestState(S nextState, float duration)
      Requests the state machine to transition into the specified state at the earliest opportunity. Once active, the state will remain active for the specified duration (in seconds).

      Returns a boolean indicating if the state machine allows a transition from the preceding state in the queue into the requested state.

    • forceState

      public void forceState(S nextState)
      Forces this state machine into the specified state, clearing the queue so that the requested state becomes active during the next frame update.

    • update

      public void update(float deltaTime)
      Updates this state machine based on the elapsed relative time, as specified by the Updatable interface.
      Specified by:
      update in interface Updatable

    • getActiveState

      public S getActiveState()

    • getActiveStateTimer

      public Timer getActiveStateTimer()