childFile1.setParent(parentFile1);
childFile2.setParent(parentFile1);
parentFile1.getAlternatives().add(childFile1);
parentFile1.getAlternatives().add(childFile2);
server.save(parentFile1);
server.save(childFile1);
server.save(childFile2);
// As a workaround for the problem, the child objects can be deleted first
//server.delete(childFile1);