OoasTools

/**

  *

  *                      OOAS Compiler

  *

  *       Copyright 2015, AIT Austrian Institute of Technology.

  * This code is based on the C# Version of the OOAS Compiler, which is

  * copyright 2015 by the Institute of Software Technology, Graz University

  * of Technology with portions copyright by the AIT Austrian Institute of

  * Technology. All rights reserved.

  *

  * SEE THE "LICENSE" FILE FOR THE TERMS UNDER WHICH THIS FILE IS PROVIDED.

  *

  * If you modify the file please update the list of contributors below to in-

  * clude your name. Please also stick to the coding convention of using TABs

  * to do the basic (block-level) indentation and spaces for anything after

  * that. (Enable the display of special chars and it should be pretty obvious

  * what this means.) Also, remove all trailing whitespace.

  *

  * Contributors:

  *               Willibald Krenn (AIT)

  *               Stephan Zimmerer (AIT)

  *               Markus Demetz (AIT)

  *               Christoph Czurda (AIT)

  *

  */

package org.momut.ooas.visitors;

import java.util.HashSet;

import org.momut.ooas.ast.AstNodeTypeEnum;

import org.momut.ooas.ast.IAst;

import org.momut.ooas.ast.identifiers.Identifier;

import org.momut.ooas.ast.identifiers.IdentifierKind;

import org.momut.ooas.ast.identifiers.MainModule;

import org.momut.ooas.ast.identifiers.TypeIdentifier;

import org.momut.ooas.ast.types.ListType;

import org.momut.ooas.ast.types.MapType;

import org.momut.ooas.ast.types.OoActionSystemType;

import org.momut.ooas.ast.types.TupleType;

import org.momut.ooas.ast.types.Type;

import org.momut.ooas.parser.ParserError;

import org.momut.ooas.parser.ParserState;

import org.momut.ooas.utils.exceptions.ArgumentException;

/// <summary>

/// Requires: ResolveOpaque

///

/// Checks whether types have been defined in a sane way (no self refs etc.)

/// </summary>

public final class OoaTypesVisitor extends OoaCompleteAstTraversalVisitor

{

        private void Error(Type aType, String p)

        {

                ParserError error = new ParserError(m_ParserState.filename,

                                aType.identifier().line(), aType.identifier().column(), p);

                m_ParserState.AddErrorMessage(error);

        }

        HashSet<Type> typesSeen = new HashSet<Type>();

        @Override

        public void visit(MainModule mainModule)

        {

                for (Identifier x: mainModule.symbolTable().symbolList())

                {

                        if (x.kind() == IdentifierKind.TypeIdentifier)

                                x.Accept(this);

                }

        }

        @Override

        protected void VisitAstElement(IAst element, IAst parent)

        {

                if (element.nodeType() != AstNodeTypeEnum.type)

                        m_visited.add(element);

                super.VisitAstElement(element, parent);

        }

        @Override

        public void visit(TypeIdentifier typeIdentifier)

        {

                typesSeen.clear();

                super.visit(typeIdentifier);

        }

        private interface Action<T extends Type> {

                void doIt(T param);

        }

        /* Does the check for recursion */

        private <T extends Type> void CheckForRecursion(T aType, String Message, Action<T> toCall)

        {

                if (typesSeen.contains(aType))

                {

                        Error(aType, Message);

                        return;

                }

                typesSeen.add(aType);

                try

                {

                        toCall.doIt(aType);

                }

                finally

                {

                        typesSeen.remove(aType);

                }

        }

        /* see whether a tuple-type includes itself */

        public void HackUntilCSharp4(TupleType t)

        { super.visit(t); }

        @Override

        public void visit(TupleType tupleType)

        {

                this.<TupleType>CheckForRecursion(tupleType,

                                String.format("Tuple contains itself: '%s' (Recursive definitions not allowed.)",

                                                tupleType.toString()),

                                new Action<TupleType>(){

                                        @Override

                                        public void doIt(TupleType param) {

                                                HackUntilCSharp4(param);

                                }}); // (x) => HackUntilCSharp4(x));

        }

        /* see whether a list-type includes itself */

        public void HackUntilCSharp4(ListType t)

        { super.visit(t); }

        @Override

        public void visit(ListType listType)

        {

                this.<ListType>CheckForRecursion(listType,

                                String.format("List contains itself: '%s' (Recursive definitions not allowed.)",

                                                listType.toString()),

                                new Action<ListType>(){

                                        @Override

                                        public void doIt(ListType param) {

                                                HackUntilCSharp4(param);

                                }}); // (x) => HackUntilCSharp4(x));

        }

        /* see whether a map-type includes itself */

        public void HackUntilCSharp4(MapType t)

        { super.visit(t); }

        @Override

        public void visit(MapType mapType)

        {

                this.<MapType>CheckForRecursion(mapType,

                                String.format("Map contains itself: '%s' (Recursive definitions not allowed.)",

                                                mapType.toString()),

                                new Action<MapType>(){

                                        @Override

                                        public void doIt(MapType param) {

                                                HackUntilCSharp4(param);

                                        }}); // (x) => HackUntilCSharp4(x));

        }

        @Override

        public void visit(OoActionSystemType ooActionSystemType)

        {

                // do not go into classes..

        }

        public OoaTypesVisitor(ParserState aState)

        {

                super (aState, true);

                if (aState == null)

                        throw new ArgumentException();

        }

}