smcperlgenerator.java

SMC takes a state machine stored in a .sm file and generates a State pattern in twelve programming l

//
// The contents of this file are subject to the Mozilla Public
// License Version 1.1 (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.mozilla.org/MPL/
//
// Software distributed under the License is distributed on an
// "AS IS" basis, WITHOUT WARRANTY OF ANY KIND, either express or
// implied. See the License for the specific language governing
// rights and limitations under the License.
//
// The Original Code is State Machine Compiler (SMC).
//
// The Initial Developer of the Original Code is Charles W. Rapp.
// Portions created by Charles W. Rapp are
// Copyright (C) 2005 - 2007. Charles W. Rapp.
// All Rights Reserved.
//
// Port to Python by Francois Perrad, [e-mail]
// Copyright 2004, Francois Perrad.
// All Rights Reserved.
//
// Contributor(s):
//   Eitan Suez contributed examples/Ant.
//   (Name withheld) contributed the C# code generation and
//   examples/C#.
//   Francois Perrad contributed the Python code generation and
//   examples/Python.
//   Chris Liscio contributed the Objective-C code generation
//   and examples/ObjC.
//
// RCS ID
// $Id: SmcPerlGenerator.java,v 1.9 2008/03/21 14:03:16 fperrad Exp $
//
// CHANGE LOG
// (See the bottom of this file.)
//

package net.sf.smc;

import java.io.PrintStream;
import java.util.ArrayList;
import java.util.Iterator;
import java.util.List;

/**
 * Visits the abstract syntax tree, emitting Perl code.
 * @see SmcElement
 * @see SmcCodeGenerator
 * @see SmcVisitor
 *
 * @author Francois Perrad
 */

public final class SmcPerlGenerator
    extends SmcCodeGenerator
{
//---------------------------------------------------------------
// Member methods
//

    public SmcPerlGenerator(String srcfileBase)
    {
        super (srcfileBase, "{0}{1}_sm.{2}", "pm");
    } // end of SmcPerlGenerator(String)

    public void visit(SmcFSM fsm)
    {
        String packageName = fsm.getPackage();
        String context = fsm.getContext();
        String rawSource = fsm.getSource();
        String startState = fsm.getStartState();
        List<SmcMap> maps = fsm.getMaps();
        List<SmcTransition> transitions;
        List<SmcParameter> params;
        String transName;
        int index;

        _source.println("# DO NOT EDIT.");
        _source.println(
            "# generated by smc (http://smc.sourceforge.net/)");
        _source.print("# from file : ");
        _source.print(_srcfileBase);
        _source.println(".sm");
        _source.println();

        // Dump out the raw source code, if any.
        if (rawSource != null && rawSource.length () > 0)
        {
            _source.println(rawSource);
            _source.println();
        }

        // If a package has been specified,
        if (packageName != null && packageName.length() > 0)
        {
              context = packageName + "::" + context;
              startState = packageName + "::" + startState;
        }

        _source.println("use strict;");
        _source.println("use warnings;");
        _source.println();
        _source.println("use DFA::Statemap;");

        // Do user-specified imports now.
        for (String imp: fsm.getImports())
        {
            _source.print("use ");
            _source.print(imp);
            _source.println(";");
        }

        // Declare the inner state class.
        _source.println();
        _source.print("package ");
        _source.print(context);
        _source.println("State;");
        _source.println("    use base qw(DFA::Statemap::State);");
        _source.println();
        _source.println("    use Carp;");
        _source.println();

        _source.println("    sub Entry {}");
        _source.println();
        _source.println("    sub Exit {}");
        _source.println();

        // Get the transition list.
        // Generate the default transition definitions.
        transitions = fsm.getTransitions();
        for (SmcTransition trans: transitions)
        {
            params = trans.getParameters();

            // Don't generate the Default transition here.
            if (trans.getName().equals("Default") == false)
            {
                _source.print("    sub ");
                _source.print(trans.getName());
                _source.println(" {");

                // If this method is reached, that means that
                // this transition was passed to a state which
                // does not define the transition. Call the
                // state's default transition method.
                _source.println("        shift->Default(@_);");

                _source.println("    }");
                _source.println();
            }
        }

        // Generate the overall Default transition for all maps.
        _source.println("    sub Default {");
        _source.println("        my $self = shift;");
        _source.println("        my ($fsm) = @_;");

        if (Smc.isDebug() == true)
        {
            _source.println(
                "        if ($fsm->getDebugFlag()) {");
            _source.println(
                "            my $fh = $fsm->getDebugStream();");
            _source.println(
                "            print $fh \"TRANSITION   : Default\\n\";");
            _source.println("        }");
        }

        if (Smc.isDebug() == true)
        {
            _source.println(
                "        confess \"TransitionUndefinedException\\n\",");
        }
        else
        {
            _source.println(
                "        croak \"TransitionUndefinedException\\n\",");
        }
        _source.println(
            "            \"State: \", $fsm->getState()->getName(),\"\\n\",");
        _source.println(
            "            \"Transition: \", $fsm->getTransition(),\"\\n\";");
        _source.println("    }");

        // Have each map print out its source code now.
        for (SmcMap map: maps)
        {
            map.accept(this);
        }

        // End of context class.
        _source.println();

        // The context class contains all the state classes as
        // inner classes, so generate the context first rather
        // than last.
        _source.print("package ");
        _source.print(context);
        _source.println("_sm;");
        _source.println(
            "    use base qw(DFA::Statemap::FSMContext);");
        _source.println();
        _source.println("    use Carp;");
        _source.println();

        // Generate the context class' constructor.
        _source.println("    sub new {");
        _source.println("        my $proto = shift;");
        _source.println("        my $class = ref($proto) || $proto;");
        _source.println("        my $self = $class->SUPER::new();");
        _source.println("        my ($owner) = @_;");
        _source.println("        $self->{_owner} = $owner;");

        _source.print("        $self->setState($");
        _source.print(startState);
        _source.println(");");

        // Execute the start state's entry actions.
        _source.print("        $");
        _source.print(startState);
        _source.println("->Entry($self);");

        _source.println("        return $self;");
        _source.println("    }");
        _source.println();

        // Generate the transition methods.
        for (SmcTransition trans: transitions)
        {
            transName = trans.getName();
            params = trans.getParameters();

            if (transName.equals("Default") == false)
            {
                _source.print("    sub ");
                _source.print(transName);
                _source.println(" {");
                _source.println("        my $self = shift;");

                // Save away the transition name in case it is
                // need in an UndefinedTransitionException.
                _source.print(
                    "        $self->{_transition} = '");
                _source.print(transName);
                _source.println("';");

                _source.print("        $self->getState()->");
                _source.print(transName);
                _source.print("($self");

                if (params.size() != 0)
                {
                    _source.print(", @_");
                }
                _source.println(");");
                _source.println(
                    "        $self->{_transition} = undef;");

                _source.println("    }");
                _source.println();
            }
        }

        // getOwner() method.
        _source.println("    sub getOwner {");
        _source.println("        my $self = shift;");
        _source.println("        return $self->{_owner};");
        _source.println("    }");
        _source.println();

        _source.println("1;");

        return;
    } // end of visit(SmcFSM)

    public void visit(SmcMap map)
    {
        List<SmcTransition> definedDefaultTransitions;
        SmcState defaultState = map.getDefaultState();
        String packageName = map.getFSM().getPackage();
        String context = map.getFSM().getContext();
        String mapName = map.getName();
        List<SmcState> states = map.getStates();

        // If a package has been specified,
        if (packageName != null && packageName.length() > 0)
        {
              mapName = packageName + "::" + mapName;
              context = packageName + "::" + context;
        }

        // Initialize the default transition list to all the
        // default state's transitions.
        if (defaultState != null)
        {
            definedDefaultTransitions =
                    defaultState.getTransitions();
        }
        else
        {
            definedDefaultTransitions =
                new ArrayList<SmcTransition>();
        }

        // Declare the map class.
        _source.println();
        _source.print("package ");
        _source.print(mapName);
        _source.println(";");
        _source.println();
        _source.println("use vars qw(");

        // Declare each of the state class member data.
        for (SmcState state: states)
        {
            _source.print("    $");
            _source.println(state.getInstanceName());
        }
        _source.println("    $Default");
        _source.println(");");

        // Declare the map default state class.
        _source.println();
        _source.print("package ");
        _source.print(mapName);
        _source.println("_Default;");
        _source.print("    use base qw(");
        _source.print(context);
        _source.println("State);");

        // Declare the user-defined default transitions first.
        for (SmcTransition transition: definedDefaultTransitions)
        {
            transition.accept(this);
        }

        // If -reflect was specified, then generate the
        // _transitions table.
        if (Smc.isReflection() == true)
        {
            List<SmcTransition> allTransitions =
                map.getFSM().getTransitions();
            String transName;
            int transDefinition;

            // Generate the getTransitions() method.
            _source.println();
            _source.println("    sub getTransitions {");
            _source.println("        return {");

            // Now place all transition names and states into the
            // map.
            for (SmcTransition transition: allTransitions)
            {
                transName = transition.getName();

                // If the transition is defined in this map's
                // default state, then the value is 2.
                if (definedDefaultTransitions.contains(
                        transition) == true)
                {
                    transDefinition = 2;
                }
                // Otherwise the value is 0 - undefined.
                else
                {
                    transDefinition = 0;
                }

                _source.print("            '");
                _source.print(transName);
                _source.print("' => ");
                _source.print(transDefinition);
                _source.println(",");
            }
            _source.println("        };");
            _source.println("    }");
        }

        // Have each state now generate its code. Each state
        // class is an inner class.
        for (SmcState state: states)
        {
            state.accept(this);
        }

        // Initialize the map class.
        _source.println();
        _source.print("package ");
        _source.print(mapName);
        _source.println(';');
        _source.println();
        _source.println("sub BEGIN {");

        for (SmcState state: states)
        {
            _source.print("    $");
            _source.print(state.getInstanceName());
            _source.print(" = new ");
            _source.print(mapName);
            _source.print('_');
            _source.print(state.getClassName());
            _source.print("('");
            _source.print(mapName);
            _source.print('.');