FSM.java

/*
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 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
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 * particular file as subject to the "Classpath" exception as provided
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 * This code is distributed in the hope that it will be useful, but WITHOUT
 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
 * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
 * version 2 for more details (a copy is included in the LICENSE file that
 * accompanied this code).
 *
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package org.jboss.com.sun.corba.se.spi.orbutil.fsm;

/**
 * An FSM is used to represent an instance of a finite state machine which has a transition function represented by an
 * instance of StateEngine. An instance of an FSM may be created either by calling StateEngine.makeFSM( startState ) on
 * a state engine, or by extending FSMImpl and using a constructor. Using FSMImpl as a base class is convenient if
 * additional state is associated with the FSM beyond that encoded by the current state. This is especially convenient
 * if an action needs some additional information. For example, counters are best handled by special actions rather than
 * encoding a bounded counter in a state machine. It is also possible to create a class that implements the FSM
 * interface by delegating to an FSM instance created by StateEngine.makeFSM.
 * 
 * @author Ken Cavanaugh
 */
public interface FSM
{
    /**
     * Get the current state of this FSM.
     */
    public State getState();

    /**
     * Perform the action and transition to the next state based on the current state of the FSM and the input.
     */
    public void doIt(Input in);
}

// end of FSM.java