Extend of CSVExporter throws NPE - jsf

Question

I work with Primefaces 4-SNAPSHOT and I have some DataTables with <h:graphicImage> in them which I would like to export into different documents.
The fix that is desribed in p:dataExporter does not recognize p:cellEditor
which is supplied by BalusC works fine for the ExcelExporter, but does not work in the same way fot the CSVExporter.
I get NPE when I try to create the document.
I tried to remove the first lines of Code from the Extend-Class, because I have no CellEditor-Elements. This sort of works. It has no NPEs bus this gives me a document with the toString() of the graphicImage and the alt value.
The Extended-Class is this:
public class ExtendedCSVExporter extends CSVExporter
{
#Override
protected String exportValue(FacesContext context, UIComponent component)
{
if (component instanceof HtmlGraphicImage)
{
return (String) component.getAttributes().get("alt");
}
else
{
return super.exportValue(context, component);
}
}
}
And I call it like described in the referenced topic
public void exportPDF(DataTable table, String filename) throws IOException {
FacesContext context = FacesContext.getCurrentInstance();
Exporter exporter = new ExtendedCSVExporter();
exporter.export(context, table, filename, false, false, "UTF-8", null, null);
context.responseComplete();
}
The column of the Table looks like this:
<p:column sortBy="state">
<f:facet name="header">
<h:outputText value="State">
</f:facet>
<h:graphicImage id="stateImg" name="state.png" library="icons" value="#{bean.state} />
<p:tooltip for="stateImg" value="Allowed" showEffect="fade" hideEffect="fade" />
</p:column>
For the Excel export this works fine, and the value which is taken for the image is the value of the tooltip because the graphic image has no alt-value.
But this does not work for CSV files
What I get in my document for pageOnly is:
"javax.faces.component.html.HtmlGraphicImage#23e645d8AltText"
For the whole Table I get a NPE
Any suggestions how to fix this?

Answer 1

Okay I know have found a solution to my problem.
I just override the HtmlGraphicImage.
I modified the Extended-Class so the GraphicImage always returns an empty String and I fetch the value of the tooltip.
So the Extende-Class looks like this:
public class ExtendedCSVExporter extends CSVExporter
{
#Override
protected String exportValue(FacesContext context, UIComponent component)
{
if (component instanceof HtmlGraphicImage)
{
return "";
}
else
{
return super.exportValue(context, component);
}
}
}