access form data in a jsp
<form name="f" action="<c:url value='j_spring_security_check'/>" method="POST">
      <table>
        <tr><td>User:</td><td><input type='text' name='j_username' value='<c:if test="${not empty param.login_error}"><c:out value="${SPRING_SECURITY_LAST_USERNAME}"/></c:if>'/></td></tr>
        <tr><td>Password:</td><td><input type='password' name='j_password'></td></tr>
        <s:select list="#{'Gross':'Gross','PP1A':'PP1A','PP1B':'PP1B','PP1C':'PP1C'}" label="Component"
                    name="component" headerKey="-1" headerValue="-- Please Select --"/>

        <tr><td colspan='2'><input name="submit" type="submit" value="Login"></td></tr>
        <tr><td colspan='2'><input name="reset" type="reset"></td></tr>
      </table>

    </form>

form-login login-page="/Login.jsp" authentication-failure-url="/Login.jsp?login_error=1"
                    default-target-url="/common/home.jsp"/>