import org.springframework.util.Assert;
import org.springframework.web.bind.annotation.PathVariable;
import org.springframework.web.bind.annotation.RequestBody;
import org.springframework.web.bind.annotation.RequestMapping;
import org.springframework.web.bind.annotation.RestController;
<BUG>import rx.Observable;</BUG>
import javax.servlet.http.HttpServletRequest;
<BUG>import java.util.List;
import java.util.stream.Collectors;</BUG>
import static org.springframework.hateoas.mvc.ControllerLinkBuilder.methodOn;

import org.springframework.util.Assert;
import org.springframework.web.bind.annotation.PathVariable;
import org.springframework.web.bind.annotation.RequestBody;
import org.springframework.web.bind.annotation.RequestMapping;
import org.springframework.web.bind.annotation.RestController;
import javax.servlet.http.HttpServletRequest;
import java.util.List;
import java.util.concurrent.CompletableFuture;
import java.util.stream.Collectors;
import static org.springframework.hateoas.mvc.ControllerLinkBuilder.methodOn;
