Refactorization.java

/* 
  Copyright (C) 2013 Raquel Pau and Albert Coroleu.
 
 Walkmod is free software: you can redistribute it and/or modify
 it under the terms of the GNU Lesser General Public License as published by
 the Free Software Foundation, either version 3 of the License, or
 (at your option) any later version.
 
 Walkmod is distributed in the hope that it will be useful,
 but WITHOUT ANY WARRANTY; without even the implied warranty of
 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 GNU Lesser General Public License for more details.
 
 You should have received a copy of the GNU Lesser General Public License
 along with Walkmod.  If not, see <http://www.gnu.org/licenses/>.*/
package org.walkmod.javalang.ast;

import java.util.LinkedList;
import java.util.List;
import java.util.Map;

import org.walkmod.javalang.ast.expr.FieldAccessExpr;
import org.walkmod.javalang.ast.expr.NameExpr;
import org.walkmod.javalang.ast.expr.ThisExpr;
import org.walkmod.javalang.visitors.VoidVisitorAdapter;

public class Refactorization {

   /**
    * Generic method to rename a SymbolDefinition variable/parameter.
    * @param n variable to rename.
    * @param newName new name to set.
    * @return if the rename procedure has been applied successfully.
    */
   public boolean refactorVariable(SymbolDefinition n, final String newName) {
      Map<String, SymbolDefinition> scope = n.getVariableDefinitions();

      if (!scope.containsKey(newName)) {
  
         if (n.getUsages() != null) {
            List<SymbolReference> usages = new LinkedList<SymbolReference>(n.getUsages());
            
            VoidVisitorAdapter<?> visitor = new VoidVisitorAdapter<Object>() {
               @Override
               public void visit(NameExpr nexpr, Object ctx) {
                  Map<String, SymbolDefinition> innerScope = nexpr.getVariableDefinitions();
                  if (innerScope.containsKey(newName)) {
                     nexpr.getParentNode().replaceChildNode(nexpr, new FieldAccessExpr(new ThisExpr(), newName));
                  } else {
                     nexpr.getParentNode().replaceChildNode(nexpr, new NameExpr(newName));
                  }
               }

               @Override
               public void visit(FieldAccessExpr nexpr, Object ctx) {
                  nexpr.getParentNode().replaceChildNode(nexpr,
                        new FieldAccessExpr(nexpr.getScope(), nexpr.getTypeArgs(), newName));
               }
            };

            for (SymbolReference usage : usages) {
               Node aux = (Node) usage;

               aux.accept(visitor, null);

            }
         }

         return true;
      }
      return false;
   }
   
}