在具体介绍之前，先了解下什么是JPA
JPA全称JavaPersistence API.JPA通过JDK5.0注解或XML描述对象－关系表的映射关系，并将运行期的实体对象持久化到数据库中。
下面具体介绍怎么配置
第一种方式（最简单最快速的实现连接 推荐使用第二种）
1.引入jar包
pom.xml配置：
<dependency>
<groupId>mysql</groupId>
<artifactId>mysql-connector-java</artifactId>
</dependency> <dependency>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-starter-data-jpa</artifactId>
</dependency>
2.配置application.properties
关于application.properties
springboot中允许修改默认的配置，一般在resource文件下添加application.properties文件，修改相关的配置
########################################################
###datasource
########################################################
spring.datasource.url = jdbc:mysql://123.206.228.200:3306/test
spring.datasource.username = shijunjie
spring.datasource.password = *******
spring.datasource.driverClassName = com.mysql.jdbc.Driver
spring.datasource.max-active=20
spring.datasource.max-idle=8
spring.datasource.min-idle=8
spring.datasource.initial-size=10
########################################################
### Java Persistence Api
########################################################
# Specify the DBMS
spring.jpa.database = MYSQL
# Show or not log for each sql query
spring.jpa.show-sql = true
# Hibernate ddl auto (create, create-drop, update)
spring.jpa.hibernate.ddl-auto = create-drop
# Naming strategy
#[org.hibernate.cfg.ImprovedNamingStrategy #org.hibernate.cfg.DefaultNamingStrategy]
spring.jpa.hibernate.naming-strategy = org.hibernate.cfg.ImprovedNamingStrategy
# stripped before adding them to the entity manager)
spring.jpa.properties.hibernate.dialect= org.hibernate.dialect.MySQL5Dialect
3.编写实体类
package me.shijunjie.entity; import javax.persistence.Column;
import javax.persistence.Entity;
import javax.persistence.GeneratedValue;
import javax.persistence.Id;
import javax.persistence.Table; @Entity //加入这个注解，Demo就会进行持久化了
@Table(name="t_demo")
public class Demo { public Demo() {
} public Demo(long id, String name) {
this.id = id;
this.name = name;
} @Id
@GeneratedValue
private long id; @Column(name="tname")
private String name; public long getId() {
return id;
} public void setId(long id) {
this.id = id;
} public String getName() {
return name;
} public void setName(String name) {
this.name = name;
} }
4.编写DAO
package me.shijunjie.dao;
import org.springframework.data.jpa.repository.JpaRepository;
import me.shijunjie.entity.Demo;
public interface DemoDao extends JpaRepository<Demo, Long> {
}
5.编写Service接口及其实现类
接口：
package me.shijunjie.service;
import me.shijunjie.entity.Demo;
public interface DemoService {
public void save(Demo demo);
}
实现类：
package me.shijunjie.service.impl; import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.stereotype.Service; import me.shijunjie.dao.DemoDao;
import me.shijunjie.entity.Demo;
import me.shijunjie.service.DemoService; @Service
public class DemoServiceImpl implements DemoService { @Autowired
private DemoDao demoDao; public void save(Demo demo){
demoDao.save(demo);
}
}
6.编写Controller
package me.shijunjie.controller; import javax.annotation.Resource; import org.springframework.web.bind.annotation.RequestMapping;
import org.springframework.web.bind.annotation.RestController; import me.shijunjie.entity.Demo;
import me.shijunjie.service.DemoService; @RestController
@RequestMapping("/demo")
public class DemoController { @Resource
private DemoService demoService; /** * 测试保存数据方法. * @return */ @RequestMapping("/save")
public String save(){
Demo d = new Demo();
d.setName("Angel");
demoService.save(d);//保存数据.
return "ok.DemoController.save"; }
}
7.编写入口
package me.shijunjie.controller; import org.springframework.boot.SpringApplication;
import org.springframework.boot.autoconfigure.SpringBootApplication;
import org.springframework.boot.context.web.SpringBootServletInitializer;
import org.springframework.boot.orm.jpa.EntityScan;
import org.springframework.context.annotation.ComponentScan;
import org.springframework.data.jpa.repository.config.EnableJpaRepositories;
import org.springframework.scheduling.annotation.EnableScheduling; @ComponentScan(basePackages={"me.shijunjie"}) // 扫描该包路径下的所有spring组件
@EnableJpaRepositories("me.shijunjie.dao") // JPA扫描该包路径下的Repositorie
@EntityScan("me.shijunjie.entity") // 扫描实体类
@SpringBootApplication
@EnableScheduling
public class App extends SpringBootServletInitializer{
public static void main(String[] args) {
SpringApplication.run(App.class, args);
}
}
输入spring-boot:run进行测试
打开浏览器输入http://localhost:8080/demo/save
查看数据库表中是否存入了数据
运行成功！
第二种方式（推荐）