DocumentFactory factory = DocumentUtil.createDocumentFactory(this.manager, session);
String url = ServletHelper.getWebappURI(request);
if (factory.isDocument(url)) {
Node node = factory.getFromURL(url).getRepositoryNode();
if (node.isCheckedOutBySession(session)) {
node.checkin();
}
}
else {
throw new RuntimeException("The URL [" + url + "] doesn't represent a document.");
}