java - spring-data-jpa @RestController @Repository 可选的奇怪行为

Question

我的@RestController

@GetMapping("/projects/{project_id}")
public Project getProjectById(@PathVariable(value = "project_id") UUID projectId) {
    return projectRepository.findById(projectId).orElseThrow(Util.notFound(projectId));
}

我的项目存储库是

@Repository
public interface ProjectRepository extends PagingAndSortingRepository<Project, UUID> {
}

public class Util {

    static Supplier<ResourceNotFoundException> notFound(UUID msg) {
        log.error(msg + " not found");
        return () -> new ResourceNotFoundException(msg + " not found");
    }
}

当我执行 GET {{host}}/projects/{{projId1}} 时，它会返回结果。然而，在日志中，它显示。

org.hibernate.SQL: select project0_.id as id1_4_0_, proje...  
o.h.type.descriptor.sql.BasicBinder: binding parameter [1] as [OTHER]  
ERROR: projectId not found . 

为什么orElseThrow总是在数据返回后执行？

Answer 1

修复你的Util

public class Util {
    static Supplier<ResourceNotFoundException> notFound(UUID msg) {
        return () -> {
            log.error(msg + " not found");
            return new ResourceNotFoundException(msg + " not found");
        };
    }
}

只有在实际抛出时才需要记录。