springboot -- JPA简单运用

1、导入相关依赖

<dependency>
		<groupId>org.springframework.boot</groupId>
			<artifactId>spring-boot-starter-data-jpa</artifactId>
		</dependency>
		<dependency>
			<groupId>org.springframework.boot</groupId>
			<artifactId>spring-boot-starter-jdbc</artifactId>
		</dependency>
		<dependency>
			<groupId>mysql</groupId>
			<artifactId>mysql-connector-java</artifactId>
			<version>8.0.11</version>
			<scope>runtime</scope>
		</dependency>

2、配置文件（application.yml）

spring:
  datasource:
    url: jdbc:mysql://localhost:3306/abc?serverTimezone=UTC&useUnicode=true&characterEncoding=utf8&useSSL=false
    driver-class-name: com.mysql.cj.jdbc.Driver
    username: root
    password: admin
  jpa:
    hibernate:
      ddl-auto: update
    show-sql: true
    

3、创建实体类

package com.example.bean;

import javax.persistence.Column;
import javax.persistence.Entity;
import javax.persistence.GeneratedValue;
import javax.persistence.GenerationType;
import javax.persistence.Id;
import javax.persistence.Table;

@Entity
@Table(name="_user")
public class User {
	@Id
	@GeneratedValue(strategy = GenerationType.IDENTITY)
	private Integer id;
	
	private String lastName;

	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;
	}
	
	
}

4、创建实现JPA的接口

package com.example.dao;

import org.springframework.data.jpa.repository.JpaRepository;

import com.example.bean.User;

public interface UserResposity extends JpaRepository<User, Integer>{

}

5、调用测试

package com.example.controller;

import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.stereotype.Controller;
import org.springframework.web.bind.annotation.GetMapping;
import org.springframework.web.bind.annotation.PathVariable;
import org.springframework.web.bind.annotation.RestController;

import com.example.bean.User;
import com.example.dao.UserResposity;

@RestController
public class UserController {
	@Autowired
	UserResposity userResposity;
	
	@GetMapping("/user/{id}")
	public User get(@PathVariable("id") int id){
		return userResposity.findOne(id);
	}
	
	@GetMapping("/user")
	public User add(User user){
		return userResposity.saveAndFlush(user);
	}
}