int count = 0;
debug("Number of execution threads: %s", nThreads);
try {
for (final String file : listSelectedFiles()) {
completionService.submit(new Runnable() {
public void run() {
Document document = documentFactory.createDocuments(file);
debug("Selected file: %s [header style: %s]", document.getFile(), document.getHeaderDefinition());
if (document.isNotSupported()) {
warn("Unknown file extension: %s", document.getFile());