title: Concatenate strings in JSP EL?
body: <p>I have a List of beans, each of which has a property which itself is a List of email addresses.</p>
  
  <pre><code>&lt;c:forEach items="${upcomingSchedule}" var="conf"&gt;
      &lt;div class='scheduled' title="${conf.subject}" id="scheduled&lt;c:out value="${conf.id}"/&gt;"&gt;
      ...
      &lt;/div&gt;
  &lt;/c:forEach&gt;
  </code></pre>
  
  <p>This renders one <code>&lt;div&gt;</code> per bean in the List.</p>
  
  <p>For the sublist, what I'd like to be able to do is to concatenate each of the entries in the list to form a single String, to be displayed as a part of the <code>&lt;div&gt;</code>'s <code>title</code> attribute. Why? Because we are using a javascript library (mootools) to turn this <code>&lt;div&gt;</code> into a floating tool tip, and the library turns the <code>title</code> into the text of the tooltip.</p>
  
  <p>So, if <code>${conf.subject}</code> was "Subject", ultimately I'd like the <code>title</code> of the <code>&lt;div&gt;</code> to be "Subject: blah@blah.com, blah2@blah2.com, etc.", containing all of the email addresses of the sub-list.</p>
  
  <p>How can I do this using JSP EL? I'm trying to stay away from putting scriptlet blocks in the jsp file.</p>