一、Spring-Data-Jpa概念
- JPA(Java Persistence API)定义了一系列对象持久化的标准,目前实现这一规范的产品有Hibernate、TopLink等。
- Spring Data JPA 框架,主要针对的就是 Spring 唯一没有简化到的业务逻辑代码,至此,开发者连仅剩的实现持久层业务逻辑的工作都省了,唯一要做的,就只是声明持久层的接口,其他都交给 Spring Data JPA 来帮你完成!
二、自动生成表
2.1 pom.xml,按代码提示键进入编辑视图选择jpa和mysql
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就会自动引入依赖
<dependency> <groupId>org.springframework.boot</groupId> <artifactId>spring-boot-starter-data-jpa</artifactId> </dependency> <dependency> <groupId>mysql</groupId> <artifactId>mysql-connector-java</artifactId> <scope>runtime</scope> </dependency>
2.2 配置application.properties
server.port=8088
spring.jpa.show-sql=true
spring.datasource.driver-class-name=com.mysql.jdbc.Driver
spring.datasource.url=jdbc:mysql://localhost:3306/db_boot
spring.datasource.username=root
spring.datasource.password=
spring.jpa.generate-ddl=true
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spring.jpa.generate-ddl=true一定要加
2.3 编写实体
package com.shyroke.entity; import javax.persistence.Column; import javax.persistence.Entity; import javax.persistence.GeneratedValue; import javax.persistence.Id; import javax.persistence.Table; @Entity @Table(name="t_book") public class Book { @Id @GeneratedValue private Integer id; @Column(length=100) private String bookName; public Integer getId() { return id; } public void setId(Integer id) { this.id = id; } public String getBookName() { return bookName; } public void setBookName(String bookName) { this.bookName = bookName; } }
2.4 运行HelloWorldApplication
package com.shyroke; import org.springframework.boot.SpringApplication; import org.springframework.boot.autoconfigure.SpringBootApplication; @SpringBootApplication public class HelloWorldApplication { public static void main(String[] args) { SpringApplication.run(HelloWorldApplication.class, args); } }
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数据库中自动生成表