//
// Licensed to the Apache Software Foundation (ASF) under one
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// 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
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//
package com.cloud.utils.fsm;
public interface StateListener<S, E, V> {
/**
* Event is triggered before state machine transition finished.
* If you want to get the state of vm before state machine changed, you need to listen on this event
* @param oldState VM's old state
* @param event that triggered this VM state change
* @param newState VM's new state
* @param vo the VM instance
* @param opaque host id
* @return
*/
public boolean preStateTransitionEvent(S oldState, E event, S newState, V vo, boolean status, Object opaque);
/**
* Event is triggered after state machine transition finished
* @param transition The Transition fo the Event
* @param vo the VM instance
* @param status the state transition is allowed or not
* @return
*/
public boolean postStateTransitionEvent(StateMachine2.Transition<S, E> transition, V vo, boolean status, Object opaque);
}