JPA连接数据库

1.pom.xml 配置maven依赖

<!-- MYSQL --> 
<dependency> 
       <groupId>mysql</groupId> 
       <artifactId>mysql-connector-java</artifactId> 
</dependency> 
    <!-- 2.Spring Boot JPA --> 
<dependency> 
     <groupId>org.springframework.boot</groupId> 
     <artifactId>spring-boot-starter-data-jpa</artifactId> 
</dependency>

2.属性配置文件（application.properties）

spring.datasource.url=jdbc:mysql://localhost:3306/springboot 
spring.datasource.username=root 
spring.datasource.password=bwyp 
spring.datasource.driver-class-name=com.mysql.jdbc.Driver 
#JPA 
spring.jpa.hibernate.ddl-auto=update 
spring.jpa.show-sql=true

3.Jpa.java

package cn.wuyang.springboot.entity; 
 
import javax.persistence.Column; 
import javax.persistence.Entity; 
import javax.persistence.GeneratedValue; 
import javax.persistence.Id; 
import javax.persistence.Table; 
 
@Entity 
@Table(name="jpa") 
public class Jpa { 
 
    @Id                  //主键 
    @GeneratedValue      //自增 
    private int jpa_id; 
 
    @Column(name="jpa_name") 
    private String jpa_name; 
 
    public int getJpa_id() { 
        return jpa_id; 
    } 
 
    public void setJpa_id(int jpa_id) { 
        this.jpa_id = jpa_id; 
    } 
 
    public String getJpa_name() { 
        return jpa_name; 
    } 
 
    public void setJpa_name(String jpa_name) { 
        this.jpa_name = jpa_name; 
    } 
 
} 
 

运行会自动生成对应表

4.JpaController.java

package cn.wuyang.springboot.controller; 
 
import java.util.List; 
 
import org.springframework.beans.factory.annotation.Autowired; 
import org.springframework.web.bind.annotation.PathVariable; 
import org.springframework.web.bind.annotation.RequestMapping; 
import org.springframework.web.bind.annotation.RequestParam; 
import org.springframework.web.bind.annotation.RestController; 
 
import cn.wuyang.springboot.dao.JpaDao; 
import cn.wuyang.springboot.entity.Jpa; 
 
@RestController 
@RequestMapping("/jpa") 
public class JpaController { 
 
    @Autowired 
    private JpaDao jpaDao; 
 
    /** 
     * 获取列表 
     * @return 
     */ 
    @RequestMapping("/list") 
    public List<Jpa> jpaList(){ 
        return jpaDao.findAll(); 
    } 
 
    /** 
     * 保存 
     * @param jpa_name 
     * @return 
     */ 
    @RequestMapping("/add") 
    public Jpa add(@RequestParam("jpa_name") String jpa_name) { 
        Jpa jpa = new Jpa(); 
        jpa.setJpa_name(jpa_name); 
        return jpaDao.save(jpa); 
    } 
 
    /** 
     * 根据id查询 
     * @param id 
     * @return 
     */ 
    @RequestMapping("/findbyid/{id}") 
    public Jpa findbyid(@PathVariable("id") Integer id) { 
        return jpaDao.findOne(id); 
    } 
 
} 

5.JpaDao.java

package cn.wuyang.springboot.dao; 
 
import org.springframework.data.jpa.repository.JpaRepository; 
 
import cn.wuyang.springboot.entity.Jpa; 
 
/** 
 * 继承JpaRepository 
 * @author wuyang 
 * 
 */ 
public interface JpaDao extends JpaRepository<Jpa, Integer> { 
}