JPA是什么? JPA(Java Persistence API)是Sun官方提出的Java持久化规范. 为Java开发人员提供了一种对象/关联映射工具来管理Java应用中的关系数据. 它的出现是为了简化现有的持久化开发工作和整合ORM技术. 结束各个ORM框架各自为营的局面.
JPA 其实是一种规范，它的实现中比较出名的是 Hibernate 框架；

1、pom 引入依赖：

<dependency> <groupId>org.springframework.boot</groupId> <artifactId>spring-boot-starter-data-jpa</artifactId> </dependency> <dependency> <groupId>org.springframework.boot</groupId> <artifactId>spring-boot-starter-web</artifactId> </dependency> <dependency> <groupId>mysql</groupId> <artifactId>mysql-connector-java</artifactId> <scope>runtime</scope> <version>5.1.18</version> </dependency> <dependency> <groupId>com.alibaba</groupId> <artifactId>druid-spring-boot-starter</artifactId> <version>1.1.10</version> </dependency>

2、添加配置文件

#数据库连接信息
spring.datasource.type=com.alibaba.druid.pool.DruidDataSource
spring.datasource.username=root
spring.datasource.password=521hui
spring.datasource.url=jdbc:mysql://localhost:3306/test
#JPA设置
spring.jpa.show-sql=true
spring.jpa.database=mysql
spring.jpa.database-platform=mysql
spring.jpa.hibernate.ddl-auto=update
spring.jpa.properties.hibernate.dialect=org.hibernate.dialect.MySQL57Dialect

3、编写 bean

@Entity(name = "t_book")public class Book { @Id @GeneratedValue(strategy = GenerationType.IDENTITY) private Integer id; private String name; private String author; public Integer getId() { return id; } public void setId(Integer id) { this.id = id; } public String getName() { return name; } public void setName(String name) { this.name = name; } public String getAuthor() { return author; } public void setAuthor(String author) { this.author = author; } @Override public String toString() { return "Book{" + "id=" + id + ", name='" + name + '\'' + ", author='" + author + '\'' + '}'; }}

4、编写 接口

public interface BookDao extends JpaRepository<Book,Integer> {
}

5、启动程序，数据库创建表

6、进行 CRUD 测试

@Autowired BookDao bookDao; @Test void testInsert() { Book book = new Book(); book.setName("孔雀翎"); book.setAuthor("古龙"); bookDao.save(book); } @Test void testupdate() { Book book = new Book(); book.setName("笑傲江湖"); book.setAuthor("金庸"); book.setId(1); bookDao.saveAndFlush(book); } @Test void testdelete() { bookDao.deleteById(1); } @Test void testFind() { System.out.println(bookDao.findById(4).toString()); }

以上就是本文的全部内容，希望对大家的学习有所帮助，也希望大家多多支持。