javax.persistence 不包含在 spring 数据 jpa 中？

Question

I just created a maven project with this dependency

<dependency>
            <groupId>org.springframework.data</groupId>
            <artifactId>spring-data-jpa</artifactId>
            <version>2.2.1.RELEASE</version>
        </dependency>

but I realized that all these classes are not found:

import javax.persistence.*

so I have to change the dependency to

 <dependency>
                <groupId>javax.persistence</groupId>
                <artifactId>javax.persistence-api</artifactId>
                <version>2.2</version>
            </dependency>

which I find it weird because last update is from Aug 21, 2017

there is no spring dependency that includes javax.persistence????

Answer 1

Spring Data JPA itself isn't an implementation of the JPA specification. It is an abstraction built on top of JPA that requires a JPA implementation, typically Hibernate, to function. The JPA implementation provides the javax.persistence classes.

If you're using Spring Boot's Data JPA starter, it has dependencies on both Spring Data JPA and Hibernate. Hibernate then has a dependency on the javax.persistence API which makes its classes available to your application's code.