wicket download output stream - wicket

Question

I want to download csv file , i take the response content and write to it , apprently wicket write after me and the content iam getting is the page html where it should be my csv
I have seen in the example the usage of throw new AbortException();
I am using version 6.7 , do you know if my version wicket has somthing instead of it ?
or rather I am doing somthing wrong ....
can you please help me ...
add(new Link<Void>("export") {
#Override
public void onClick() {
WebResponse response = (WebResponse) getResponse();
response.setAttachmentHeader("export.csv");
response.setContentType("text/csv");
OutputStream out = getResponse().getOutputStream();
try {
c.exportData(dataSource.getListForExport(), columns, out);
} catch (Exception ex) {
System.err.println(ex);
}
}
});
public <T> void exportData(List<T> list, List<IGridColumn<IDataSource<T>, T, String>> columns, OutputStream outputStream)
throws IOException {
long startTime = System.nanoTime();
PrintWriter out = new PrintWriter(new OutputStreamWriter(outputStream, Charset.forName(characterSet)));
try {
if (isExportHeadersEnabled()) {
boolean first = true;
for (IGridColumn<IDataSource<T>, T, String> col : columns) {
if (first) {
first = false;
} else {
out.print(delimiter);
System.out.println(delimiter);
}
if (col.getId().equals("checkBox")) {
continue;
}
out.print(quoteValue(col.getId()));
System.out.println(col.getId());
}
out.print("\r\n");
System.out.println("\r\n");
}
Iterator<? extends T> rowIterator = list.iterator();
while (rowIterator.hasNext()) {
T row = rowIterator.next();
boolean first = true;
for (IGridColumn<IDataSource<T>, T, String> col : columns) {
if (first) {
first = false;
} else {
out.print(delimiter);
System.out.println(delimiter);
}
if (col.getId().equals("checkBox")) {
continue;
}
Object o = (new PropertyModel<>(row, col.getId())).getObject();// ((AbstractColumn<T,
if (o != null) {
Class<?> c = o.getClass();
String s;
IConverter converter = Application.get().getConverterLocator().getConverter(c);
if (converter == null) {
s = o.toString();
} else {
s = converter.convertToString(o, Session.get().getLocale());
}
out.print(quoteValue(s));
System.out.println(quoteValue(s));
}
}
out.print("\r\n");
System.out.println("\r\n");
}
} catch (Exception ex) {
System.out.println(ex);
} finally {
System.out.println(out);
out.close();
// measure
System.out.print(System.nanoTime() - startTime);
}
}

Answer 1

The best way to do this is using dynamic resources. I'll suggest you to read chapter "Resource managment with Wicket" of this magnific free Wicket guide: https://code.google.com/p/wicket-guide/.
Here you have a similar example given in this guide in the section "Custom resources".
public class RSSProducerResource extends AbstractResource {
#Override
protected ResourceResponse newResourceResponse(Attributes attributes) {
ResourceResponse resourceResponse = new ResourceResponse();
resourceResponse.setContentType("text/xml");
resourceResponse.setTextEncoding("utf-8");
resourceResponse.setWriteCallback(new WriteCallback()
{
#Override
public void writeData(Attributes attributes) throws IOException
{
OutputStream outputStream = attributes.getResponse().getOutputStream();
Writer writer = new OutputStreamWriter(outputStream);
SyndFeedOutput output = new SyndFeedOutput();
try {
output.output(getFeed(), writer);
} catch (FeedException e) {
throw new WicketRuntimeException("Problems writing feed to response...");
}
}
});
return resourceResponse;
}
// method getFeed()...
}
And then you need to add the link in the desired page or component:
add(new ResourceLink("rssLink", new RSSProducerResource()));