Advanced Features Made Easy - Stripes...and Java Web Development is Fun Again - page 188

Parsing multipart/form-data

Correctly parsing data that arrives in the multipart/form-data
MIME type is surprisingly difficult. Instead of reinventing the
wheel, Stripes delegates this unpleasant piece of work to third-
party libraries that have already solved the problem. The Stripes
distribution includes two such libraries: Apache Commons File-
Upload ∗ and COS. †

Stripes automatically uses the implementation that it finds in
the class path. To use Commons File Upload, copy commons-
fileupload.jar and commons-io.jar to the WEB-INF/lib directory. For
COS, use cos.jar . If Stripes finds both libraries, Commons FileU-
pload is chosen.

So, how do you decide between Commons FileUpload and
COS? Basically, the advantage of COS is that it's only one JAR
file instead of two. However, the license for Commons FileU-
pload is more permissive; it caches small files in memory instead
of writing them to disk, improving performance; and, unlike
COS, Commons FileUpload is still being maintained.

Of course, if you know of another implementation, you can
plug it in. The strategy for handling multipart form data is
represented in Stripes by the MultipartWrapper interface. This is
an extension, so placing your implementation in an extension
package would have Stripes use it automatically.

∗. http://jakarta.apache.org/commons/fileupload/

†. http://servlets.com/cos/

Download email_19/web/WEB-INF/jsp/message_details.jsp

<c:if test="${not empty actionBean.message.attachments}">
<div> Attachments: </div>
<div>
<c:forEach var="attachment"
items="${actionBean.message.attachments}">
<s:link event="downloadAttachment"
beanclass="stripesbook.action.MessageDetailsActionBean">
<s:param name="attachmentId" value="${attachment.id}"/>
${attachment.fileName}
</s:link>
(${attachment.size} bytes)
<br/>
</c:forEach>
</div>
</c:if>