def update
        @user_existed = User.find_by_user_name(:user_name => params[:user_name])
        @user = User.find_or_create_by_user_name(:user_name => params[:user_name])
        @user.user_name = params[:user_name]
        @user.first_name = params[:first_name]
        @user.last_name = params[:last_name]
        @user.password = params[:password]
        @user.save
        if @user_existed.nil?
                flash[:message] = "New User: #{@user.first_name} #{@user.last_name} has been created."
        else
                flash[:message] = "Existing User: #{@user.first_name} #{@user.last_name} has been updated."
        end
        redirect_to :action => 'list'
  end