您的位置:首页 > 编程语言 > Java开发

springboot整合JPA过程解析

2020-03-11 17:52 621 查看

这篇文章主要介绍了springboot整合JPA过程解析,文中通过示例代码介绍的非常详细,对大家的学习或者工作具有一定的参考学习价值,需要的朋友可以参考下

接下来具体看看是怎么弄的。

1、新建一个springboot项目,选择web、data jdbc、data jpa、mysql driver。

2、建立以下目录及结构:

pom.xml

<?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 https://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>2.2.4.RELEASE</version>
<relativePath/> <!-- lookup parent from repository -->
</parent>
<groupId>com.gong</groupId>
<artifactId>springbootjpa</artifactId>
<version>0.0.1-SNAPSHOT</version>
<name>springbootjpa</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-jdbc</artifactId>
</dependency>
<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>
<version>5.1.41</version>
<scope>runtime</scope>
</dependency>
<dependency>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-starter-test</artifactId>
<scope>test</scope>
<exclusions>
<exclusion>
<groupId>org.junit.vintage</groupId>
<artifactId>junit-vintage-engine</artifactId>
</exclusion>
</exclusions>
</dependency>
</dependencies>

<build>
<plugins>
<plugin>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-maven-plugin</artifactId>
</plugin>
</plugins>
</build>

</project>

3、在application.yml中配置连接数据库和jpa相关配置

spring:
datasource:
url: jdbc:mysql://192.168.124.22:3306/jpa
username: root
password: 123456
driver-class-name: com.mysql.jdbc.Driver
jpa:
hibernate:
#更新或者创建数据表结构
ddl-auto: update
#控制台显示SQL
show-sql: true

4、新建一个entity包,新建实体类User.java

package com.gong.springbootjpa.entity;

import com.fasterxml.jackson.annotation.JsonIgnoreProperties;

import javax.persistence.*;

//使用JPA注解配置映射关系
@Entity //告诉JPA这是一个实体类(和数据表映射的类)
@Table(name = "tbl_user") //@Table来指定和哪个数据表对应;如果省略默认表名就是user;
@JsonIgnoreProperties(value = {"hibernateLazyInitializer","handler"})
public class User {

@Id //这是一个主键
@GeneratedValue(strategy = GenerationType.IDENTITY)//自增主键
private Integer id;

@Column(name = "last_name",length = 50) //这是和数据表对应的一个列
private String lastName;
@Column //省略默认列名就是属性名
private String email;

public Integer getId() {
return id;
}

public void setId(Integer id) {
this.id = id;
}

public String getLastName() {
return lastName;
}

public void setLastName(String lastName) {
this.lastName = lastName;
}

public String getEmail() {
return email;
}

public void setEmail(String email) {
this.email = email;
}
}

5、新建一个repository包,新建一个UserRepository.java

package com.gong.springbootjpa.repository;

import com.gong.springbootjpa.entity.User;
import org.springframework.data.jpa.repository.JpaRepository;

//继承JpaRepository来完成对数据库的操作,在JdbcRepository中指定实体类,数据库中主键对应的java类型
public interface UserRepository extends JpaRepository<User,Integer> {
}

6、新建一个controller包,新建一个UserController.java

经过上述配置之后,我们就可以直接利用UserRepository中的一些方法进行数据库的操作啦,是不是很方便。

package com.gong.springbootjpa.controller;

import com.gong.springbootjpa.entity.User;
import com.gong.springbootjpa.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;

@RestController
public class UserController {

@Autowired
UserRepository userRepository;

@GetMapping("/user/{id}")
public User getUser(@PathVariable("id") Integer id){
User user = userRepository.getOne(id);
return user;
}

@GetMapping("/user")
public User insertUser(User user){
User save = userRepository.save(user);
return save;
}

}

7、启动服务器

插入一条数据:

查询一条数据:

以上就是本文的全部内容,希望对大家的学习有所帮助

您可能感兴趣的文章:

内容来自用户分享和网络整理,不保证内容的准确性,如有侵权内容,可联系管理员处理 点击这里给我发消息
标签:  spring boot 整合 JPA