context.cxx

Vovida 社区开源的 SIP 协议源码

/* ====================================================================
 * The Vovida Software License, Version 1.0 
 * 
 * Copyright (c) 2000 Vovida Networks, Inc.  All rights reserved.
 * 
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions
 * are met:
 * 
 * 1. Redistributions of source code must retain the above copyright
 *    notice, this list of conditions and the following disclaimer.
 * 
 * 2. Redistributions in binary form must reproduce the above copyright
 *    notice, this list of conditions and the following disclaimer in
 *    the documentation and/or other materials provided with the
 *    distribution.
 * 
 * 3. The names "VOCAL", "Vovida Open Communication Application Library",
 *    and "Vovida Open Communication Application Library (VOCAL)" must
 *    not be used to endorse or promote products derived from this
 *    software without prior written permission. For written
 *    permission, please contact [e-mail].
 *
 * 4. Products derived from this software may not be called "VOCAL", nor
 *    may "VOCAL" appear in their name, without prior written
 *    permission of Vovida Networks, Inc.
 * 
 * THIS SOFTWARE IS PROVIDED "AS IS" AND ANY EXPRESSED OR IMPLIED
 * WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
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 * USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH
 * DAMAGE.
 * 
 * ====================================================================
 * 
 * This software consists of voluntary contributions made by Vovida
 * Networks, Inc. and many individuals on behalf of Vovida Networks,
 * Inc.  For more information on Vovida Networks, Inc., please see
 * <http://www.vovida.org/>.
 *
 */


static const char* const Context_cxx_Version = 
    "$Id: Context.cxx,v 1.2 2001/08/10 04:02:04 icahoon Exp $";


#include "global.h"
#include "Context.hxx"
#include "StateInterface.hxx"


using Vocal::Behavioral::Context;
using Vocal::Behavioral::StateInterface;
using Vocal::Behavioral::Stimulus;


Context::Context()
    :	myState(0),
    	myStartState(0),
	myStopState(0)
{
}


Context::~Context()
{
}


void	    	
Context::reset() throw()
{
    if ( myState )
    {
    	myState->exit();
    }
    
    myState = myStartState;
    myState->enter();
}


void	    	
Context::reset(StateInterface & state) throw()
{
    if ( myState )
    {
    	myState->exit();
    }
    
    myState = &state;
    myState->enter();
}

void	    	
Context::startState(StateInterface & state)
{
    myStartState = &state;
    
    if ( myState == 0 )
    {
    	myState = myStartState;
    	myStartState->enter();
    }
}


bool	    	
Context::inStartState() const
{
    return ( myState == myStartState );
}


void	    	
Context::stopState(StateInterface & state)
{
    myStopState = &state;
}


bool	    	
Context::inStopState() const
{
    return ( myState == myStopState );
}


void        	
Context::stimulate(const Stimulus & stimulus) throw ()
{
    if ( myState )
    {
    	myState = &(myState->stimulate(stimulus));
    }
}


ostream &       
Context::writeTo(ostream & out) const
{
    return ( out << name() );
}


bool
Context::verifyState(const StateInterface & state)
{
    return ( &state == myState );
}