springboot之jpa（简述）

1、maven引入jar包（jpa和mysql）

<dependency>
    <groupId>org.springframework.boot</groupId>
    <artifactId>spring-boot-starter-data-jpa</artifactId>
</dependency>
<dependency>
 <groupId>mysql</groupId>
 <artifactId>mysql-connector-java</artifactId>
</dependency>

 2、配置文件

spring.datasource.url=jdbc:mysql://localhost:3306/test
spring.datasource.username=root
spring.datasource.password=root
spring.datasource.driver-class-name=com.mysql.jdbc.Driver

server.port=8080

 3、创建实体类（示例）

import javax.persistence.Entity;
import javax.persistence.GeneratedValue;
import javax.persistence.Id;
import javax.persistence.Table;
import java.io.Serializable;

@Entity
@Table(name="student")
public class Student implements Serializable {
    private static final long serialVersionUID = 1L;
    @Id
    @GeneratedValue
    private Integer sid;
    private String sname;
    private Integer sage;
    private String ssex;

    public Integer getSid() {
        return sid;
    }

    public void setSid(Integer sid) {
        this.sid = sid;
    }

    public String getSname() {
        return sname;
    }

    public void setSname(String sname) {
        this.sname = sname;
    }

    public Integer getSage() {
        return sage;
    }

    public void setSage(Integer sage) {
        this.sage = sage;
    }

    public String getSsex() {
        return ssex;
    }

    public void setSsex(String ssex) {
        this.ssex = ssex;
    }
}

 4、创建对应实体的接口

import com.demo.entity.Student;
import org.springframework.data.jpa.repository.JpaRepository;

//1、这个类中自带一些简单的增删改查方法，可以直接调用

public interface StudentRepository extends JpaRepository<Student,Integer> {
　//2、也支持执行sql语句（例如）
  @Query("from Student where sage = ?1")
  List<Student> getStudentsBySage(@Param("sage") Integer sage);

 //3、支持根据方法名的查询（例如）
 Student findBySid(Integer sid);
}

详细介绍：

https://blog.csdn.net/ityouknow/article/details/52688664