Erro 500

at br.com.alura.gerenciador.servlet.UnicaEntradaServlet.service(UnicaEntradaServlet.java:35)
GRAVE: Servlet.service() for servlet [br.com.alura.gerenciador.servlet.UnicaEntradaServlet] in context with path [/gerenciador] threw exception [java.lang.ClassNotFoundException: br.com.alura.gerenciador.acao.LoginForm] with root cause

java.lang.ClassNotFoundException: br.com.alura.gerenciador.acao.LoginForm

Aqui está a minha classe UnicaEntradaervlet @WebServlet("/entrada") public class UnicaEntradaServlet extends HttpServlet { private static final long serialVersionUID = 1L;

protected void service(HttpServletRequest request, HttpServletResponse response) 
        throws ServletException, IOException {

    String paramAcao = request.getParameter("acao");

    String nomeDaClasse = "br.com.alura.gerenciador.acao." + 
        paramAcao;

    String nome = null;
    try {
        Class classe = Class.forName(nomeDaClasse); 
        Acao acao = (Acao) classe.newInstance();
        try {
            nome = acao.executa(request,response);
        } catch (ServletException | IOException | ParseException e) {
            // TODO Auto-generated catch block
            e.printStackTrace();
        }
    } catch (ClassNotFoundException | 
            InstantiationException | 
            IllegalAccessException e) {
        throw new ServletException(e);
    }

    String[] tipoEEndereco = nome.split(":");
    if(tipoEEndereco[0].equals("forward")) {
        RequestDispatcher rd = 
            request.getRequestDispatcher("WEB-INF/view/" + tipoEEndereco[1]);
        rd.forward(request, response);
    } else {
        response.sendRedirect(tipoEEndereco[1]);
    }        
}

}