Here's my code:
<%@ page import="java.io.*,java.util.*,java.sql.*"%>
<%@ page import="javax.servlet.http.*,javax.servlet.*" %>
<%@ taglib uri="http://java.sun.com/jsp/jstl/core" prefix="c"%>
<%@ taglib uri="http://java.sun.com/jsp/jstl/sql" prefix="sql"%>
Followed by the html file. jstl-1.2.jar is located in the WEB-INF folder. That is the only explanation I've found anywhere else for why this shouldn't work, so I don't understand why I am still having this problem.
The version of JSP I was using was not compatible with the version of JSTL.