SpringBoot集成JPA用法笔记

       

       

今天给大家整理SpringBoot集成JPA用法。希望对大家能有所帮助！

1. 搭建SpringBoot项目

       

       

       

       

       

       

2. 新建配置文件 application.yml

server:port: 8090spring:#通用的数据源配置  datasource:driverClassName: com.mysql.jdbc.Driverurl: jdbc:mysql://localhost:3306/test?useSSL=false&useUnicode=true&characterEncoding=utf8username: rootpassword: rootjpa:#将默认的存储引擎切换为 InnoDB    database-platform: org.hibernate.dialect.MySQL5InnoDBDialect#配置在日志中打印出执行的 SQL 语句信息。    show-sql: true    hibernate:#配置指明在程序启动的时候要删除并且创建实体类对应的表      # validate 加载 Hibernate 时，验证创建数据库表结构      # create 每次加载 Hibernate ，重新创建数据库表结构，这就是导致数据库表数据丢失的原因。      # create-drop 加载 Hibernate 时创建，退出是删除表结构（退出是指退出sessionFactory）      # update 加载 Hibernate 自动更新数据库结构      # none 不启用      ddl-auto: none

3、新建用户实体类 UserInfoDAO.java

package my.springboot.jpa.entity;import javax.persistence.*;import java.util.Date;/** * 用户表实体 * **/@Entity@Table(name = "userinfo")public class UserInfoDAO {@Id@GeneratedValue(strategy = GenerationType.IDENTITY)private  Integer id;@Columnprivate String userName;@Columnprivate Integer age;@Column(length = 500)private String address;@Column(name = "create_date")private Date createDate;@Column(name = "create_user")private String createUser;
public Integer getId() {return id;    }
public void setId(Integer id) {this.id = id;    }
public String getUserName() {return userName;    }
public void setUserName(String userName) {this.userName = userName;    }
public Integer getAge() {return age;    }
public void setAge(Integer age) {this.age = age;    }
public String getAddress() {return address;    }
public void setAddress(String address) {this.address = address;    }
public Date getCreateDate() {return createDate;    }
public void setCreateDate(Date createDate) {this.createDate = createDate;    }
public String getCreateUser() {return createUser;    }
public void setCreateUser(String createUser) {this.createUser = createUser;    }}

4、仓库接口类 UserIfoRepository

package my.springboot.jpa.dao;import my.springboot.jpa.entity.UserInfoDAO;import org.springframework.data.jpa.repository.JpaRepository;import org.springframework.stereotype.Repository;/** * 仓库接口类 UserIfoRepository **/@Repositorypublic interface UserIfoRepository extends JpaRepository<UserInfoDAO, Integer> {}

5、新建测试用户类 UserInfoTest.java

package my.springboot.jpa;
import my.springboot.jpa.dao.UserIfoRepository;import my.springboot.jpa.entity.UserInfoDAO;import org.junit.Test;import org.junit.runner.RunWith;import org.springframework.beans.factory.annotation.Autowired;import org.springframework.boot.test.context.SpringBootTest;import org.springframework.test.context.junit4.SpringRunner;import java.util.Date;import java.util.List;import java.util.Optional;
/** * 测试UserInfo用法 **/@RunWith(SpringRunner.class)@SpringBootTestpublic class UserInfoTest {@Autowired    UserIfoRepository userIfoRepository;
@Test    public void test() {//插入用户测试        UserInfoDAO dao = new UserInfoDAO();        dao.setUserName("小明");        dao.setAge(32);        dao.setCreateDate(new Date());        dao.setCreateUser("管理员");        dao.setAddress("苏州");userIfoRepository.save(dao);        UserInfoDAO dao2 = new UserInfoDAO();        dao2.setUserName("小张");        dao2.setAge(35);        dao2.setCreateDate(new Date());        dao2.setCreateUser("管理员");        dao2.setAddress("南京");userIfoRepository.save(dao2);
// 查询多条记录 打印        List<UserInfoDAO> list = userIfoRepository.findAll();for (UserInfoDAO item : list) {
            System.out.println("姓名：" + item.getUserName() + " 年龄：" + item.getAge());        }// 查询单个记录        Optional<UserInfoDAO> mo = userIfoRepository.findById(2);        System.out.println(mo.get().getUserName());//更新操作        mo.get().setUserName("小明123");userIfoRepository.save(mo.get());        System.out.println(mo.get().getUserName());//删除记录        userIfoRepository.delete(mo.get());    }}

6、配置生成数据表

package my.springboot.jpa;import org.springframework.boot.SpringApplication;import org.springframework.boot.autoconfigure.SpringBootApplication;import org.springframework.boot.autoconfigure.domain.EntityScan;import org.springframework.data.jpa.repository.config.EnableJpaRepositories;
@SpringBootApplication@EntityScan(basePackages = {"my.springboot.jpa.entity"})@EnableJpaRepositories(basePackages = {"my.springboot.jpa.dao"})public class JpaApplication {public static void main(String[] args) {        SpringApplication.run(JpaApplication.class, args);    }}



@EntityScan(basePackages = {"my.springboot.jpa.entity"})@EnableJpaRepositories(basePackages = {"my.springboot.jpa.dao"})

7、项目结构图

       

       

IT技术分享社区

个人博客网站：https://programmerblog.xyz