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.ast.statements;

import java.util.LinkedList;

import org.momut.ooas.ast.IScope;

import org.momut.ooas.ast.expressions.Expression;

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

import org.momut.ooas.parser.SymbolTable;

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

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

///////////////////////////////////////////////

///  Blocks

///

public abstract class Block extends Statement implements IScope

{

        private final SymbolTable m_symbols;

        private LinkedList<Statement> m_statements;

        private Expression m_filter; /*gets transformed to guarded command in resolvevisitor!*/

        private IScope m_parentScope;

        public SymbolTable symbols() { return m_symbols; }

        public LinkedList<Statement> statements() { return m_statements; }

        public Expression filter() { return m_filter; }

        public Block(StatementKind aKind, int aline, int apos)

        {

                super (aKind, aline, apos);

                m_symbols = new SymbolTable();

                m_statements = new LinkedList<Statement>();

        }

        public Block(Block toCopy)

        {

                super (toCopy);

                m_symbols = new SymbolTable(toCopy.m_symbols);

                m_statements = new LinkedList<Statement>(toCopy.m_statements);

                m_parentScope = toCopy.m_parentScope;

                m_filter = toCopy.m_filter;

        }

        @Override

        public /*override*/ Statement Clone()

        {

                throw new NotImplementedException();

        }

        public void AddStatement(Statement toAdd)

        {

                m_statements.addLast(toAdd);

                checkParentScope(toAdd);

        }

        private void checkParentScope(Statement toAdd) {

                if (toAdd instanceof IScope) {

                        final IScope child = (IScope) toAdd;

                        if (child.GetParentScope() == null)

                                child.SetParentScope(this);

                        else if (child.GetParentScope() != this)

                                throw new InternalCompilerException("Internal error: Statement added to block has parent set to different object.");

                }

        }

        public void SetStatements(LinkedList<Statement> newStatements)

        {

                m_statements = newStatements;

                for (final Statement s: newStatements)

                        checkParentScope(s);

        }

        public void AddIdentifier(Identifier anIdentifier)

        {

                m_symbols.AddIdentifier(anIdentifier);

        }

        @Override

        public Identifier ResolveIdentifier(String aName)

        {

                if (m_symbols.Defined(aName))

                        return m_symbols.Get(aName);

                else

                        return null;

        }

        @Override

        public IScope GetParentScope()

        {

                return m_parentScope;

        }

        @Override

        public void SetParentScope(IScope parentScope)

        {

                if (parentScope == null)

                        System.out.println("");

                m_parentScope = parentScope;

        }

        @Override

        public void AddIdentifier(Identifier anIdentifier, Object tag)

        {

                m_symbols.AddIdentifier(anIdentifier);

        }

        public void SetFilter(Expression sexpr)

        {

                m_filter = sexpr;

        }

        /** Checks whether there are no local variables etc. for this block */

        public boolean isSimpleBlock() {

                return m_symbols.size() == 0 && m_filter == null;

        }

}