<%@ taglib uri="http://java.sun.com/jsp/jstl/core"
    prefix="c" %>
<%@ page contentType="text/html;charset=UTF-8" language="java" %>

<html>
    <c:set var="username" scope="session" value="${param.username}"/>
    <c:out value="${username}"/>
    <c:remove var="username"/>
</html>