<%@ page contentType="text/html;charset=UTF-8" language="java" %>
<%@ taglib prefix="c" uri="http://java.sun.com/jsp/jstl/core" %>
...
<table>
    <c:forEach var="post" items="${posts}">
        <c:set var="post_title" value="${post.title}"/>
        <h1>${post.title}</h1>
        <tr>
            <td>
                    ${post.message}
            </td>
            <td>
                    ${post.author}
            </td>
        </tr>
    </c:forEach>
</table>
<c:url value="dosomething.html" var="post_title_uri">
    <c:param name="id" value="${post_title}"/>
</c:url>
<a href="${post_title_uri}">Click me</a>
...