FSM.java revision 608:7e06bf1dcb09 
1/*
2 * Copyright (c) 2002, 2003, Oracle and/or its affiliates. All rights reserved.
3 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
4 *
5 * This code is free software; you can redistribute it and/or modify it
6 * under the terms of the GNU General Public License version 2 only, as
7 * published by the Free Software Foundation.  Oracle designates this
8 * particular file as subject to the "Classpath" exception as provided
9 * by Oracle in the LICENSE file that accompanied this code.
10 *
11 * This code is distributed in the hope that it will be useful, but WITHOUT
12 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
13 * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
14 * version 2 for more details (a copy is included in the LICENSE file that
15 * accompanied this code).
16 *
17 * You should have received a copy of the GNU General Public License version
18 * 2 along with this work; if not, write to the Free Software Foundation,
19 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
20 *
21 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
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24 */
25
26package com.sun.corba.se.spi.orbutil.fsm ;
27
28/**
29 * An FSM is used to represent an instance of a finite state machine
30 * which has a transition function represented by an instance of
31 * StateEngine.  An instance of an FSM may be created either by calling
32 * StateEngine.makeFSM( startState ) on a state engine, or by extending FSMImpl and
33 * using a constructor.  Using FSMImpl as a base class is convenient if
34 * additional state is associated with the FSM beyond that encoded
35 * by the current state.  This is especially convenient if an action
36 * needs some additional information.  For example, counters are best
37 * handled by special actions rather than encoding a bounded counter
38 * in a state machine.  It is also possible to create a class that
39 * implements the FSM interface by delegating to an FSM instance
40 * created by StateEngine.makeFSM.
41 *
42 * @author Ken Cavanaugh
43 */
44public interface FSM
45{
46    /** Get the current state of this FSM.
47    */
48    public State getState() ;
49
50    /** Perform the action and transition to the next state based
51    * on the current state of the FSM and the input.
52    */
53    public void doIt( Input in ) ;
54}
55
56// end of FSM.java
57