Skip to main content

3 posts tagged with "spring-data-jpa"

View All Tags

通过关闭OpenEntityManagerInViewInterceptor确保当下游服务响应缓慢时不会导致数据库连接被占用完

· 3 min read
orange
orange
programmer on jvm platform

OpenEntityManagerInViewInterceptor是spring中的一个拦截器，它的作用是在整个请求上下文复用同一个EntityManager ，从而避免在一个请求中多次创建一个EntityManager, 从而提高性能.
但是如果在一个请求的处理代码中请求了下游服务，而下游服务响应缓慢，那么在下游服务响应之前，EntityManager 会一直被占用，直到整个请求处理完成，这样会导致当服务并发请求量较大时，数据库连接被占用完.
为了避免这种情况，可以通过关闭OpenEntityManagerInViewInterceptor来确保当下游服务响应缓慢时不会导致数据库连接被占用完. 下面将介绍如何关闭OpenEntityManagerInViewInterceptor.

在kotlin项目中kotlin-jpa插件导致导致null检查失效

· One min read
orange
orange
programmer on jvm platform

kotlin-jpa插件会为data class生成无参构造器，导致非空字段跳过了Null检查

@Entity
class ProjectInfo(
	var name: String,
	var code: String,
	var ownerName: String,
	var applicantName: String,
	var companyCode: String,
	var companyName: String,
	var projectType: ProjectType,
	var submitDate: LocalDateTime = LocalDateTime.now(),
	var planStartDate: LocalDate?,
	var planEndDate: LocalDate?,
	var endDate: String,
	var targetCustomers: Array<String>?,
	var formStatus: ApplicationStatus = ApplicationStatus.DRAFT,
	var projectStatus: ApplicationProjectStatus = ApplicationProjectStatus.DRAFT,
	var comments: String?
) {

	@Id
	@GeneratedValue(strategy = GenerationType.IDENTITY)
	val id: Long = -1
}