anchor.diff:      <body>
           <%@include file="snippets/nav-logged.jsp" %>
           <div class="container">
  -            <% if(request.getParameter("error") != null && !request.getParameter("error").isEmpty()){ %>
  +            <% if (request.getParameter("error") != null && !request.getParameter("error").isEmpty()) { %>
               <div class="panel panel-danger">
                   <div class="panel-heading">Error:</div>
                   <div class="panel-body">
  
positive.code: <%@ page contentType="text/html; charset=UTF-8" %>
  <%@page import="app.entity.Usuario" %>
  <%
  
negative.code:                 </div>
              </div>
              <% } %>
  
              <% if (request.getParameter("exito") != null && !request.getParameter("exito").isEmpty()) {%>
              <div class="alert alert-success">
                  Mensaje mandado con éxito a <%= u.getNombre()%>
              </div>
              <% } %>
  
              <% if (amigos) {
                      Boolean peticionEnviada = (Boolean) request.getAttribute("peticionEnviada");
                  } %>
  