POM:
<?xml version="1.0" encoding="UTF-8"?>
<project xmlns="http://maven.apache.org/POM/4.0.0" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 http://maven.apache.org/xsd/maven-4.0.0.xsd">
<modelVersion>4.0.0</modelVersion>
<parent>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-starter-parent</artifactId>
<version>2.1.7.RELEASE</version>
<relativePath/> <!-- lookup parent from repository -->
</parent>
<groupId>com.example</groupId>
<artifactId>springboot-data-jpa</artifactId>
<version>0.0.1-SNAPSHOT</version>
<name>springboot-data-jpa</name>
<description>Demo project for Spring Boot</description>
<properties>
<java.version>1.8</java.version>
</properties>
<dependencies>
<dependency>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-starter-data-jpa</artifactId>
</dependency>
<dependency>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-starter-jdbc</artifactId>
</dependency>
<dependency>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-starter-web</artifactId>
</dependency>
<dependency>
<groupId>mysql</groupId>
<artifactId>mysql-connector-java</artifactId>
<version>5.1.32</version>
</dependency>
<dependency>
<groupId>org.projectlombok</groupId>
<artifactId>lombok</artifactId>
<optional>true</optional>
</dependency>
<dependency>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-starter-test</artifactId>
<scope>test</scope>
</dependency>
<dependency>
<groupId>com.alibaba</groupId>
<artifactId>druid</artifactId>
<version>1.1.18</version>
</dependency>
<dependency>
<groupId>log4j</groupId>
<artifactId>log4j</artifactId>
<version>1.2.17</version>
</dependency>
<dependency>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-autoconfigure</artifactId>
<version>2.1.7.RELEASE</version>
</dependency>
<dependency>
<groupId>org.springframework.data</groupId>
<artifactId>spring-data-jpa</artifactId>
<version>2.1.10.RELEASE</version>
</dependency>
<dependency>
<groupId>org.springframework.data</groupId>
<artifactId>spring-data-jpa</artifactId>
<version>2.1.10.RELEASE</version>
</dependency>
</dependencies>
<build>
<plugins>
<plugin>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-maven-plugin</artifactId>
</plugin>
</plugins>
</build>
</project>
yml:
spring:
datasource:
username: root
password: root
url: jdbc:mysql://:3306/springjdbc
driver-class-name: com.mysql.jdbc.Driver
type: com.alibaba.druid.pool.DruidDataSource
jpa:
hibernate:
ddl-auto: update # 更新或者创建数据表结构
show-sql: true # 控制台显示sql
实体类:
import lombok.Data;
import javax.persistence.*;
//配置映射关系,使用jpa注解
@Entity //告诉jpa这是一个实体类(和数据表映射的类)
@Table(name = "user") //指定和哪个数据表对应,如果省略默认表名就是user
@Data
public class User {
@Id //这是一个主键
@GeneratedValue(strategy = GenerationType.IDENTITY) //自增主键
private Integer id;
@Column(name = "lastname") // 表中列名若有驼峰命名,使用该注解将驼峰字母小写
private String lastName;
@Column
private String email;
}
user详情:
注意:
DAO:
import org.springframework.data.jpa.repository.JpaRepository;
// 继承Repository来完成对数据库操作
public interface UserRepository extends JpaRepository<User,Integer> {
}
Controller:
import com.example.springbootdatajpa.entity.User;
import com.example.springbootdatajpa.repository.UserRepository;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.web.bind.annotation.GetMapping;
import org.springframework.web.bind.annotation.PathVariable;
import org.springframework.web.bind.annotation.RestController;
import java.util.Optional;
@RestController
public class UserController {
@Autowired
UserRepository userRepository;
@GetMapping("/user/{id}")
public Optional<User> getUser(@PathVariable("id") Integer id){
Optional<User> user = userRepository.findById(id);
return user;
}
@GetMapping("/user")
public User insertUser(User user){
User save = userRepository.save(user);
return save;
}
}
测试:
import org.springframework.boot.SpringApplication;
import org.springframework.boot.autoconfigure.SpringBootApplication;
@SpringBootApplication
public class SpringbootDataJpaApplication {
public static void main(String[] args) {
SpringApplication.run(SpringbootDataJpaApplication.class, args);
}
}