/*
     * (non-Javadoc)
     *
     * @see org.eclipse.gef.commands.Command#execute()
     */
    @Override
    public void execute() {
      boolean modified = false;
      if (modelManager.getContextManager() != null) {
        originalName = param.getName();
        for (IContext context : modelManager.getContextManager().getListContext()) {
          for (IContextParameter contextParameter : context.getContextParameterList()) {
            String tempSourceId = contextParameter.getSource();
            if (originalName.equals(contextParameter.getName()) && tempSourceId.equals(sourceId)) {
              contextParameter.setName(newName);

              if (contextParameter.getPrompt().equals(originalName + "?")) {
                contextParameter.setPrompt(newName + "?");
              }
              modified = true;
            }
          }
        }
        param.setName(newName);
        if (param.getPrompt().equals(originalName + "?")) {
          param.setPrompt(newName + "?");
        }
      }
      if (modified) {
        updateRelation(originalName, newName);
      }
    }
 /*
  * (non-Javadoc)
  *
  * @see org.eclipse.gef.commands.Command#undo()
  */
 @Override
 public void undo() {
   boolean modified = false;
   if (modelManager.getContextManager() != null) {
     for (IContext context : modelManager.getContextManager().getListContext()) {
       for (IContextParameter contextParameter : context.getContextParameterList()) {
         if (newName.equals(contextParameter.getName())) {
           contextParameter.setName(originalName);
           if (contextParameter.getPrompt().equals(newName + "?")) {
             contextParameter.setPrompt(originalName + "?");
           }
           modified = true;
         }
       }
     }
   }
   if (modified) {
     // it is undo, so the order changed
     updateRelation(newName, originalName);
   }
 }