public void finalizarActividad() {

    try {
      FacesContext contex = FacesContext.getCurrentInstance();
      contex
          .getExternalContext()
          .redirect(
              "http://192.168.1.102:2020/aplicacionesExternas/externa.php?idAct="
                  + act.getId()
                  + "&idSes="
                  + sesion_actual.getId()
                  + "&idCond=1&idUsu="
                  + idusu.getId());
    } catch (Exception e) {
      System.out.println("----------------------------Error---------------------------------" + e);
    }
  }