//
// Licensed to the Apache Software Foundation (ASF) under one
// or more contributor license agreements. See the NOTICE file
// distributed with this work for additional information
// regarding copyright ownership. The ASF licenses this file
// to you under the Apache License, Version 2.0 (the
// "License"); you may not use this file except in compliance
// with the License. You may obtain a copy of the License at
//
// http://www.apache.org/licenses/LICENSE-2.0
//
// Unless required by applicable law or agreed to in writing,
// software distributed under the License is distributed on an
// "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
// KIND, either express or implied. See the License for the
// specific language governing permissions and limitations
// under the License.
//
package com.cloud.utils.fsm;
import java.util.List;
import java.util.Set;
/**
*
* @param <S> State
* @param <E> Event
*/
public interface FiniteState<S, E> {
/**
* @return the state machine being used.
*/
StateMachine<S, E> getStateMachine();
/**
* get next state based on the event.
* @param event
* @return next State
*/
S getNextState(E event);
/**
* Get the states that could have traveled to the current state
* via this event.
* @param event
* @return array of states
*/
List<S> getFromStates(E event);
/**
* Get the possible events that can happen from the current state.
* @return array of events.
*/
Set<E> getPossibleEvents();
String getDescription();
}