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
  22  * or visit www.oracle.com if you need additional information or have any
  23  * questions.
  24  */
  25 
  26 package com.sun.corba.se.spi.orbutil.fsm;
  27 
  28 /**
  29  * Description goes here
  30  *
  31  * @author Ken Cavanaugh
  32  */
  33 public interface Action
  34 {
  35         /** Called by the state engine to perform an action
  36         * before a state transition takes place.  The FSM is
  37         * passed so that the Action may set the next state in
  38         * cases when that is required.  FSM and Input together
  39         * allow actions to be written that depend on the state and
  40         * input, but this should generally be avoided, as the
  41         * reason for a state machine in the first place is to cleanly
  42         * separate the actions and control flow.   Note that an
  43         * action should complete in a timely manner.  If the state machine
  44         * is used for concurrency control with multiple threads, the
  45         * action must not allow multiple threads to run simultaneously
  46         * in the state machine, as the state could be corrupted.
  47         * Any exception thrown by the Action for the transition
  48         * will be propagated to doIt.
  49         * @param FSM fsm is the state machine causing this action.
  50         * @param Input in is the input that caused the transition.
  51         */
  52         public void doIt( FSM fsm, Input in ) ;
  53 }
  54 
  55 // end of Action.java