repo.lockDirCache(), commit.getTree());
dco.setFailOnConflict(true);
try {
dco.checkout();
} catch (org.eclipse.jgit.errors.CheckoutConflictException cce) {
throw new CheckoutConflictException(dco.getConflicts(), cce);
}
// update the HEAD
RefUpdate refUpdate = repo.updateRef(Constants.HEAD, true);
refUpdate.setExpectedOldObjectId(head);
refUpdate.setNewObjectId(commit);