SpringBoot+SpringDataJpa快速上手（基本CRUD）
废话不多说直接上代码样例！附带全部内容，包含数据库以及表结构和数据
依赖
<parent>
<groupId>org.springframework.bootgroupId>
<artifactId>spring-boot-starter-parentartifactId>
<version>2.1.3.RELEASEversion>
parent>
<dependencies>
<dependency>
<groupId>org.springframework.bootgroupId>
<artifactId>spring-boot-starter-webartifactId>
dependency>
<dependency>
<groupId>org.springframework.bootgroupId>
<artifactId>spring-boot-starter-data-jpaartifactId>
dependency>
<dependency>
<groupId>mysqlgroupId>
<artifactId>mysql-connector-javaartifactId>
<version>5.1.45version>
dependency>
<dependency>
<groupId>org.projectlombokgroupId>
<artifactId>lombokartifactId>
dependency>
dependencies>
实体类
- 实体类和表的映射关系
@Entity 表示实体类
@Table 表示和表的关系 - 类中属性和表中字段的映射关系
@Id 指明主键
@GeneratedValue 主键的生成策略
@Column 属性和字段对应关系，一般是字段名和属性名相差比较大使用
package com.lianxi.jpa.pojo;
import lombok.AllArgsConstructor;
import lombok.Data;
import lombok.NoArgsConstructor;
import javax.persistence.*;
import java.util.Date;
/**
* 实体类和表的映射关系
@Entity 表示实体类
@Table 表示和表的关系
*类中属性和表中字段的映射关系
@Id 指明主键
@GeneratedValue 主键的生成策略
@Column 属性和字段对应关系，一般是字段名和属性名相差比较大使用
*/
@Entity
@Table(name ="lx_user")
@Data
@NoArgsConstructor
public class User{
// id
@Id
@GeneratedValue(strategy = GenerationType.IDENTITY)
private Long id;
// 用户名
@Column(name ="user_name")
private String userName;
// 密码
private String password;
// 姓名
private String name;
// 年龄
private Integer age;
// 性别，1男性，2女性
private Integer sex;
// 出生日期
private Date birthday;
// 创建时间
private Date created;
// 更新时间
private Date updated;
// 备注
private String note;
//用来测试保存
public User(String userName, String password, String name, Integer age, Integer sex, String note) {
this.userName = userName;
this.password = password;
this.name = name;
this.age = age;
this.sex = sex;
this.note = note;
}
//用来测试更新
public User(Long id,String userName, String password, String name, Integer age, Integer sex, String note) {
this.id=id;
this.userName = userName;
this.password = password;
this.name = name;
this.age = age;
this.sex = sex;
this.note = note;
}
}
数据库以及表
/*
SQLyog Ultimate v12.08 (64 bit)
MySQL - 5.7.32 : Database - springdata_jpa
*********************************************************************
*/
/*!40101 SET NAMES utf8 */;
/*!40101 SET SQL_MODE=''*/;
/*!40014 SET @OLD_UNIQUE_CHECKS=@@UNIQUE_CHECKS, UNIQUE_CHECKS=0 */;
/*!40014 SET @OLD_FOREIGN_KEY_CHECKS=@@FOREIGN_KEY_CHECKS, FOREIGN_KEY_CHECKS=0 */;
/*!40101 SET @OLD_SQL_MODE=@@SQL_MODE, SQL_MODE='NO_AUTO_VALUE_ON_ZERO' */;
/*!40111 SET @OLD_SQL_NOTES=@@SQL_NOTES, SQL_NOTES=0 */;
CREATE DATABASE /*!32312 IF NOT EXISTS*/`springdata_jpa` /*!40100 DEFAULT CHARACTER SET utf8 COLLATE utf8_bin */;
USE `springdata_jpa`;
/*Table structure for table `lx_user` */
DROP TABLE IF EXISTS `lx_user`;
CREATE TABLE `lx_user` (
`id` bigint(20) NOT NULL AUTO_INCREMENT,
`user_name` varchar(100) DEFAULT NULL COMMENT '用户名',
`password` varchar(100) DEFAULT NULL COMMENT '密码',
`name` varchar(100) DEFAULT NULL COMMENT '姓名',
`age` int(10) DEFAULT NULL COMMENT '年龄',
`sex` tinyint(1) DEFAULT NULL COMMENT '性别，1男性，2女性',
`birthday` date DEFAULT NULL COMMENT '出生日期',
`note` varchar(255) DEFAULT NULL COMMENT '备注',
`created` datetime DEFAULT NULL COMMENT '创建时间',
`updated` datetime DEFAULT NULL COMMENT '更新时间',
PRIMARY KEY (`id`),
UNIQUE KEY `username` (`user_name`)
) ENGINE=InnoDB AUTO_INCREMENT=14 DEFAULT CHARSET=utf8;
/*Data for the table `lx_user` */
insert into `lx_user`(`id`,`user_name`,`password`,`name`,`age`,`sex`,`birthday`,`note`,`created`,`updated`) values (1,'zhangsan1','1234567','张三',25,1,'1964-08-08','张三同学在学Java','2014-09-19 16:56:04','2014-09-21 11:24:59');
insert into `lx_user`(`id`,`user_name`,`password`,`name`,`age`,`sex`,`birthday`,`note`,`created`,`updated`) values (2,'lisi11','123456777','李四',21,1,'1995-01-01','李四同学在学Java','2014-09-19 16:56:04','2014-09-19 16:56:04');
insert into `lx_user`(`id`,`user_name`,`password`,`name`,`age`,`sex`,`birthday`,`note`,`created`,`updated`) values (3,'wangwu','123456','王五',22,1,'1994-01-01','王五同学在学php','2014-09-19 16:56:04','2014-09-19 16:56:04');
insert into `lx_user`(`id`,`user_name`,`password`,`name`,`age`,`sex`,`birthday`,`note`,`created`,`updated`) values (4,'zhangwei','123456','张伟',20,1,'1996-09-01','张伟同学在学Java','2014-09-19 16:56:04','2014-09-19 16:56:04');
insert into `lx_user`(`id`,`user_name`,`password`,`name`,`age`,`sex`,`birthday`,`note`,`created`,`updated`) values (5,'lina','123456','李娜',28,0,'1988-01-01','李娜同学在学Java','2014-09-19 16:56:04','2014-09-19 16:56:04');
insert into `lx_user`(`id`,`user_name`,`password`,`name`,`age`,`sex`,`birthday`,`note`,`created`,`updated`) values (6,'lilei','123456','李磊',23,1,'1993-08-08','李磊同学在学Java','2014-09-20 11:41:15','2014-09-20 11:41:15');
insert into `lx_user`(`id`,`user_name`,`password`,`name`,`age`,`sex`,`birthday`,`note`,`created`,`updated`) values (7,'yangmi','123456','杨幂',24,0,'1992-08-08','杨幂同学在学php','2014-09-20 11:41:15','2014-09-20 11:41:15');
insert into `lx_user`(`id`,`user_name`,`password`,`name`,`age`,`sex`,`birthday`,`note`,`created`,`updated`) values (8,'liuyan','123456','柳岩',21,0,'1995-08-08','柳岩同学在学java','2014-09-20 11:41:15','2014-09-20 11:41:15');
insert into `lx_user`(`id`,`user_name`,`password`,`name`,`age`,`sex`,`birthday`,`note`,`created`,`updated`) values (9,'liuyifei','123456','刘亦菲',18,0,'1998-08-08','刘亦菲同学在学唱歌','2014-09-20 11:41:15','2014-09-20 11:41:15');
insert into `lx_user`(`id`,`user_name`,`password`,`name`,`age`,`sex`,`birthday`,`note`,`created`,`updated`) values (10,'fanbingbing','123456','范冰冰',25,0,'1991-08-08','范冰冰同学在学java','2014-09-20 11:41:15','2014-09-20 11:41:15');
insert into `lx_user`(`id`,`user_name`,`password`,`name`,`age`,`sex`,`birthday`,`note`,`created`,`updated`) values (11,'zhengshuang','123456','郑爽',23,0,'1993-08-08','郑爽同学在学习java','2014-09-20 11:41:15','2014-09-20 11:41:15');
insert into `lx_user`(`id`,`user_name`,`password`,`name`,`age`,`sex`,`birthday`,`note`,`created`,`updated`) values (12,'tangyan','123456','唐嫣',26,0,'1990-08-08','唐嫣同学在学习java','2014-09-20 11:41:15','2014-09-20 11:41:15');
/*!40101 SET SQL_MODE=@OLD_SQL_MODE */;
/*!40014 SET FOREIGN_KEY_CHECKS=@OLD_FOREIGN_KEY_CHECKS */;
/*!40014 SET UNIQUE_CHECKS=@OLD_UNIQUE_CHECKS */;
/*!40111 SET SQL_NOTES=@OLD_SQL_NOTES */;
启动类
package com.lianxi;
import org.springframework.boot.SpringApplication;
import org.springframework.boot.autoconfigure.SpringBootApplication;
@SpringBootApplication
public class UserSpringDataJpaApplication {
public static void main(String[] args) {
SpringApplication.run(UserSpringDataJpaApplication.class,args);
}
}
application.yml
server:
port: 7184
spring:
application:
name: springData-Jpa
datasource:
driver-class-name: com.mysql.jdbc.Driver
url: jdbc:mysql://127.0.0.1:3306/springdata_jpa?characterEncoding=UTF-8
username: root
password: root
jpa:
database: mysql # 指定数据库
show-sql: true # 设置显示SQL
generate-ddl: true # 设置Generate Ddl
controller
package com.lianxi.jpa.controller;
import com.lianxi.jpa.pojo.User;
import com.lianxi.jpa.service.UserService;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.web.bind.annotation.*;
import java.util.List;
@RestController
@RequestMapping("/user")
public class UserController {
@Autowired
private UserService userService;
/**
* 查询全部
* @return
*/
@GetMapping("/findAll")
public List<User> getUserFindAll(){
List<User> userList = userService.userFindAll();
//返回结果
return userList;
}
/**
* 根据id查询
*/
@GetMapping("/{id}")
public User getUserById(@PathVariable("id") Long id){
User user = userService.findById(id);
//返回结果
return user;
}
/**
* 添加一条数据
* 为了测试方便，就用GET请求了
*/
@GetMapping("/add/add")
public String userAdd(){
//构建添加数据
User user = new User("ceshi","123456","测试1",18,1,"用来测试");
//添加
String userAdd = userService.userAdd(user);
return userAdd;
}
/**
* 删除一条数据
* 为了测试方便，就用GET请求了
*/
@GetMapping("/deleteById/{id}")
public String deleteById(@PathVariable("id") Long id){
String deleteById = userService.deleteById(id);
//返回结果
return deleteById;
}
/**
* 根据id更新一条数据
* 为了测试方便，就用GET请求了
* @param id
* @return
*/
@GetMapping("/updata/{id}")
public String updataById(@PathVariable("id") Long id){
//构建数据
User user = new User(id,"ceshi","12345666","测试1",18,1,"用来测试更新方法！！");
//调用更新方法
String updataById = userService.updataById(user);
//返回结果
return updataById;
}
}
dao
继承 JpaRepository接口提供了基本的增删改查
继承JpaSpecificationExecutor接口用于做复杂的条件查询
package com.lianxi.jpa.dao;
import com.lianxi.jpa.pojo.User;
import org.springframework.data.jpa.repository.JpaRepository;
import org.springframework.data.jpa.repository.JpaSpecificationExecutor;
/**
* JpaRepository提供了基本的增删改查
* JpaSpecificationExecutor用于做复杂的条件查询
*/
public interface UserDao extends JpaRepository<User,Long>, JpaSpecificationExecutor<User> {
}
service
package com.lianxi.jpa.service;
import com.lianxi.jpa.dao.UserDao;
import com.lianxi.jpa.pojo.User;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.stereotype.Service;
import java.util.List;
import java.util.Optional;
@Service
public class UserService {
@Autowired
private UserDao userDao;
/**
* 查询全部
* @return
*/
public List<User> userFindAll() {
List<User> userDaoAll = userDao.findAll();
return userDaoAll;
}
/**
* 根据id查询
*/
public User findById(Long id) {
User user = userDao.findById(id).get();
return user;
}
/**
* 添加一条数据
*/
public String userAdd(User user) {
try {
//保存
userDao.save(user);
return "保存成功";
} catch (Exception e) {
e.printStackTrace();
return "保存失败";
}
}
/**
* 根据id删除
* @param id
* @return
*/
public String deleteById(Long id) {
try {
//保存
userDao.deleteById(id);
return "删除成功";
} catch (Exception e) {
e.printStackTrace();
return "删除失败";
}
}
/**
* 根据id更新一条数据
* @param user
* @return
*/
public String updataById(User user) {
try {
//更新
userDao.save(user);
return "更新成功";
} catch (Exception e) {
e.printStackTrace();
return "更新失败";
}
}
}