14.7. Including or Manipulating the Tag Body Multiple Times
Rather than just including or processing the body of the tag a single time, you sometimes want to do so more than once. The ability to support multiple body inclusion lets you define a variety of iteration tags that repeat JSP fragments a variable number of times, repeat them until a certain condition occurs, and so forth. This section shows you how to build such tags.
The Tag Handler Class
Tags that process the body content multiple times should start by extending BodyTagSupport and implementing doStartTag, doEndTag, and, most importantly, doAfterBody as before. The difference lies in the return value of doAfterBody. If this method returns EVAL_BODY_TAG, the tag body is evaluated again, ...