response.setContentType("text/plain");
PrintWriter out = response.getWriter();
try {
File activeCorpus = new File(new File(Oscar3Props.getInstance().workspace, "corpora"), request.getParameter("setcorpus"));
indexerSearcher = new LuceneIndexerSearcher(true);
indexerSearcher.addDirectory(activeCorpus, new PrintWriter(System.out, true));
out.println("Corpus changed to " + request.getParameter("setcorpus") + " OK!");
} catch (Exception e) {
e.printStackTrace();
out.println("Yikes, that didn't work!");
}