I had a working export option earlier. However, in order to be able to have a export option with grouping and sorting enabled, I used the WYSIWYG examples provided, over wrote my existing library files, class files (HtmlTotalWrapper.java, ItextTotalWrapper.java,....), displaytag.properties file and changed my jsp code as shown below:

In the jsp, I am now explicitly mentioning the display table to use my custom wrapper classes that I wrote and want to use for the each kind of export. Not only are the display table tags are not using my classes (they are at the right location or path) that I would like them to use as I mention explicitly in the jsp, what I do not understand is from where the display table tag is looking or using these classes that I have not mentioned even in the default displaytag.properties file??

Excel:
SEVERE: Exception: [.DefaultDecoratorFactory] Unable to load org.displaytag.sample.decorators.HssfTotalWrapper due to a j
ang.ClassNotFoundException exception Cause: org.displaytag.sample.decorators.HssfTotalWrapper
java.lang.ClassNotFoundException: org.displaytag.sample.decorators.HssfTotalWrapper
at org.apache.catalina.loader.WebappClassLoader.loadClass(WebappClassLoader.java:1340)
at org.apache.catalina.loader.WebappClassLoader.loadClass(WebappClassLoader.java:1189)

PDF:
WARNING: Exception: [.TableTag] Unable to reset response before returning exported data. You are not using an export filter. Be sure that no other jsp tags are used before display:table or refer to the displaytag documentation on how to configure the export filter (requires j2ee 1.3).

My JSP:

...
<display:table name="sessionScope.someList" export="true" id="tmpId" class="dataTable" defaultorder="ascending" cellspacing="1">

<display:setProperty name="decorator.media.html" value="displaytag.sample.decorators.MyHtmlTotalWrapper" />

<display:setProperty name="export.pdf.decorator" value="displaytag.sample.decorators.MyITextTotalWrapper" />
<display:setProperty name="export.pdf.filename" value="result.pdf" />

<display:setProperty name="export.rtf.decorator" value="displaytag.sample.decorators.MyITextTotalWrapper" />
<display:setProperty name="export.rtf.filename" value="result.rtf" />

<display:setProperty name="export.excel.decorator" value="org.displaytag.sample.decorators.HssfTotalWrapper" />
<display:setProperty name="export.excel.filename" value="result.xls" />
<display:setProperty name="export.csv" value="true" />
<display:setProperty name="export.csv.filename" value="result.csv" />
<display:setProperty name="export.xml" value="true" />
<display:setProperty name="export.xml.filename" value="result.xml" />

<display:column ... />
<display:column ... />
<display:column ... />

</display:table>

My displaytag.properties file:

sort.behavior=list

sort.amount=list

basic.empty.showtable=true

basic.msg.empty_list=No results matched your criteria.
paging.banner.placement=top

paging.banner.onepage=<span class="pagelinks"></span>

export.types=csv excel xml pdf rtf
export.excel=true
export.csv=true
export.xml=true
export.pdf=true
export.rtf=true
export.excel.class=org.displaytag.export.excel.DefaultHssfExportView
export.pdf.class=org.displaytag.export.DefaultPdfExportView
export.rtf.class=org.displaytag.export.DefaultRtfExportView

if set, file is downloaded instead of opened in the browser window

export.[mymedia].filename=