hello ,
When i choice a file to upload, and i go to the log of gae to watch
the number of uploaded files , it write "taille : 0" and not "taille :
1" , "taille : 2" ,or ... .

TopPanel.ui.xml :
<g:AbsolutePanel ui:field="absolutePanel">
<g:Label text="Choix de la personne :"
ui:field="labPersonOrProjectChoice" />
<g:ListBox ui:field="personOrProjectChoiceList" />
<g:Label text="Affecter un projet :"
ui:field="labProjectOrPersonAffectChoice" />
<g:ListBox ui:field="projectOrPersonAffectChoiceList" />
<g:FormPanel ui:field="formPanel">
<g:FileUpload ui:field="singleUploader"/>
</g:FormPanel>
<g:Button text="SUBMIT" ui:field="button"/>
<!-- <gwtUpload:SingleUploader ui:field="singleUploader"
fileInputSize="25" /> -->
</g:AbsolutePanel>

TopPanel.java :
[...]
formPanel.setAction(GWT.getModuleBaseURL() + "SampleUploadServlet");
formPanel.setEncoding(FormPanel.ENCODING_MULTIPART);
formPanel.setMethod(FormPanel.METHOD_POST);

button.addClickHandler(new ClickHandler(){

@Override
public void onClick(ClickEvent event) {
formPanel.submit();
}});

SampleUploadServlet.java :
public void doPost(HttpServletRequest request,HttpServletResponse
response){
FileItemFactory factory = new DiskFileItemFactory();
ServletFileUpload upload = new ServletFileUpload(factory);
List<FileItem> fileItems = new ArrayList<FileItem>();

try {
fileItems = upload.parseRequest(request);
throw new
IllegalArgumentException(""+fileItems.size());

} catch (FileUploadException e) {
e.printStackTrace();
}
catch(IllegalArgumentException iae){
throw new IllegalArgumentException("taille : "+fileItems.size());
}
}

public void doGet(HttpServletRequest request,HttpServletResponse
response){
try {
super.doGet(request, response);
} catch (ServletException e) {
} catch (IOException e) {
}
}

Thanks for your request