技术分享 | 数据持久化技术（Java）

本章介绍 Web 后端开发中数据持久化技术 TKMyBatis。

TKMyBatis简介

TKMybatis 是基于 Mybatis 框架开发的一个工具，内部实现了对单表的基本数据操作，只需要简单继承 TKMybatis 提供的接口，就能够实现无需编写任何 sql 即能完成单表操作。

下面简单介绍下 MyBatis ， MyBatis 是一款优秀的持久层框架，它支持自定义 SQL、存储过程以及高级映射。MyBatis 免除了几乎所有的 JDBC 代码以及设置参数和获取结果集的工作。MyBatis 可以通过简单的 XML 或注解来配置和映射原始类型、接口和 Java POJO（Plain Old Java Objects，普通老式 Java 对象）为数据库中的记录。

详细内容请参考 https://mybatis.org/mybatis-3/zh/index.html 2

TKMyBatis快速开始

Maven依赖

<dependency>

<groupId>org.mybatis.spring.boot</groupId>

<artifactId>mybatis-spring-boot-starter</artifactId>

<version>2.1.0</version>

</dependency>

<dependency>

<groupId>tk.mybatis</groupId>

<artifactId>mapper</artifactId>

<version>4.0.3</version>

</dependency>

<dependency>

<groupId>tk.mybatis</groupId>

<artifactId>mapper-spring-boot-starter</artifactId>

<version>2.0.3</version>

</dependency>

<dependency>

<groupId>mysql</groupId>

<artifactId>mysql-connector-java</artifactId>

<scope>runtime</scope>

</dependency>

在启动类中配置 MapperScan 扫描

import org.springframework.boot.SpringApplication;
import org.springframework.boot.autoconfigure.SpringBootApplication;
import tk.mybatis.spring.annotation.MapperScan;

@SpringBootApplication

@MapperScan("com.hogwartsmini.demo.dao")

public class DemoApplication {

public static void main(String[] args) {

SpringApplication.run(DemoApplication.class, args);

}

}

实体类中使用

在实体类中，常用的注解和意义为：

Table：描述数据库表信息，主要属性有 name(表名)、schema、catalog、uniqueConstraints 等。

Id：指定表主键字段，没有属性值。

Column：描述数据库字段信息，主要属性有 name(字段名)、columnDefinition、insertable、length、nullable(是否可为空)、precision、scale、table、unique、updatable 等。

ColumnType：描述数据库字段类型，可对一些特殊类型作配置，进行特殊处理，主要属性有 jdbcType、column、typeHandler 等。

dao 中使用

创建业务 Mapper 公共接口

首先创建一个公共接口，继承 Mapper, MySqlMapper, IdsMapper 三个类，用于后续业务 Mapper 接口直接实现。

import tk.mybatis.mapper.common.IdsMapper;

import tk.mybatis.mapper.common.Mapper;

import tk.mybatis.mapper.common.MySqlMapper;

public interface MySqlExtensionMapper<T> extends Mapper<T>, MySqlMapper<T>, IdsMapper<T> {

}

创建业务 Mapper 接口

创建 HogwartsTestUserMapper.java 接口

import com.hogwartsmini.demo.common.MySqlExtensionMapper;

import com.hogwartsmini.demo.entity.HogwartsTestUser;

import org.springframework.stereotype.Repository;

@Repository

public interface HogwartsTestUserMapper extends MySqlExtensionMapper<HogwartsTestUser> {

}

Service 层中使用

新增操作

删除

修改

查询

Spring Boot 配置文件

spring:

application:

name: aitest

#数据库配置信息

datasource:

url: jdbc:mysql://localhost:3306/aitest_mini?allowMultiQueries=true&useUnicode=true&characterEncoding=UTF-8&serverTimezone=Asia/Shanghai

username: hogwarts

password: db@hogwarts

driver-class-name: com.mysql.cj.jdbc.Driver

mybatis:

mapper-locations: classpath:mapper/*.xml

type-aliases-package: com.hogwartstest.aitestmini.entity

configuration:

mapUnderscoreToCamelCase: true

logging:

level:

com.hogwartstest.aitestmini.dao: debug #打印sql

示例表结构

CREATE TABLE `hogwarts_test_user` (

`id` int NOT NULL AUTO_INCREMENT COMMENT '主键',

`user_name` varchar(50) CHARACTER SET utf8mb4 COLLATE utf8mb4_general_ci NOT NULL COMMENT '用户名',

`password` varchar(32) CHARACTER SET utf8mb4 COLLATE utf8mb4_general_ci NOT NULL COMMENT '密码',

`email` varchar(50) CHARACTER SET utf8mb4 COLLATE utf8mb4_general_ci DEFAULT NULL COMMENT '邮箱',

`auto_create_case_job_name` varchar(50) CHARACTER SET utf8mb4 COLLATE utf8mb4_general_ci DEFAULT NULL COMMENT '自动生成用例job名称 不为空时表示已经创建job',

`start_test_job_name` varchar(50) CHARACTER SET utf8mb4 COLLATE utf8mb4_general_ci DEFAULT NULL COMMENT '执行测试job名称 不为空时表示已经创建job',

`default_jenkins_id` int DEFAULT NULL COMMENT '默认Jenkins服务器',

`create_time` datetime NOT NULL COMMENT '创建时间',

`update_time` datetime NOT NULL COMMENT '更新时间',

PRIMARY KEY (`id`) USING BTREE

) ENGINE=InnoDB AUTO_INCREMENT=12 DEFAULT CHARSET=utf8mb4 COLLATE=utf8mb4_general_ci ROW_FORMAT=DYNAMIC COMMENT='用户表';

Controller 代码

import com.hogwartsmini.demo.entity.HogwartsTestUser;

import com.hogwartsmini.demo.service.HogwartsTestUserService;

import io.swagger.annotations.Api;

import io.swagger.annotations.ApiOperation;

import org.springframework.beans.factory.annotation.Autowired;

import org.springframework.web.bind.annotation.*;

import java.util.List;

/**

* @Author tlibn

* @Date 2020/7/16 17:14

**/

@Api(tags = "霍格沃兹测试学院-用户管理模块")

@RestController

@RequestMapping("hogwartsUser")

public class HogwartsTestUserDbController {

@Autowired

private HogwartsTestUserService hogwartsTestUserService;

@ApiOperation("用户注册")

@PostMapping("register")

public HogwartsTestUser register(

@RequestBody HogwartsTestUser hogwartsTestUser){

return hogwartsTestUserService.save(hogwartsTestUser);

}

@ApiOperation("用户信息修改接口")

@PutMapping()

public HogwartsTestUser updateUserInfo(

@RequestBody HogwartsTestUser hogwartsTestUser){

return hogwartsTestUserService.update(hogwartsTestUser);

}

@ApiOperation("根据用户id删除用户信息")

@DeleteMapping("{userId}")

public Integer delete(@PathVariable("userId") Integer userId){

return hogwartsTestUserService.delete(userId);

}

@ApiOperation("根据用户名查询")

@GetMapping("byName")

public List<HogwartsTestUser> getByName(

@RequestParam("userName") String userName){

HogwartsTestUser hogwartsTestUser = new HogwartsTestUser();

hogwartsTestUser.setUserName(userName);

return hogwartsTestUserService.getByName(hogwartsTestUser);

}

HogwartsTestUserService 代码

import com.hogwartsmini.demo.entity.HogwartsTestUser;

import java.util.List;

public interface HogwartsTestUserService {

/**

* 保存

* @param hogwartsTestUser

* @return

*/

HogwartsTestUser save(HogwartsTestUser hogwartsTestUser);

/**

* 更新

* @param hogwartsTestUser

* @return

*/

HogwartsTestUser update(HogwartsTestUser hogwartsTestUser);

/**

* 根据用户名查询

* @param hogwartsTestUser

* @return

*/

List<HogwartsTestUser> getByName(HogwartsTestUser hogwartsTestUser);

/**

* 根据用户id删除用户信息

* @param userId

* @return

*/

Integer delete(Integer userId);

}

HogwartsTestUserServiceImpl 代码

import com.hogwartsmini.demo.dao.HogwartsTestUserMapper;
import com.hogwartsmini.demo.entity.HogwartsTestUser;
import com.hogwartsmini.demo.service.HogwartsTestUserService;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.stereotype.Service;
import java.util.Date;
import java.util.List;
/**
* @Author tlibn
* @Date 2020/7/17 11:03
**/

@Service

public class HogwartsTestUserServiceImpl implements HogwartsTestUserService {

@Autowired
private HogwartsTestUserMapper hogwartsTestUserMapper;
/**
* 保存
*
* @param hogwartsTestUser
* @return
*/

@Override

public HogwartsTestUser save(HogwartsTestUser hogwartsTestUser) {

hogwartsTestUser.setCreateTime(new Date());

hogwartsTestUser.setUpdateTime(new Date());

hogwartsTestUserMapper.insertUseGeneratedKeys(hogwartsTestUser);

return hogwartsTestUser;

}

/**
* 更新
*
* @param hogwartsTestUser
* @return
*/
@Override
public HogwartsTestUser update(HogwartsTestUser hogwartsTestUser) {
hogwartsTestUser.setCreateTime(new Date());
hogwartsTestUser.setUpdateTime(new Date());
hogwartsTestUserMapper.updateByPrimaryKeySelective(hogwartsTestUser);
return hogwartsTestUser;
}
/**
* 根据用户名查询
*
* @param hogwartsTestUser
* @return
*/
@Override
public List<HogwartsTestUser> getByName(HogwartsTestUser hogwartsTestUser) {
List<HogwartsTestUser> hogwartsTestUserList = hogwartsTestUserMapper.select(hogwartsTestUser);
return hogwartsTestUserList;
}

/**
* 根据用户id删除用户信息
*
* @param userId
* @return
*/
@Override
public Integer delete(Integer userId) {
HogwartsTestUser hogwartsTestUser = new HogwartsTestUser();
hogwartsTestUser.setId(userId);
hogwartsTestUserMapper.delete(hogwartsTestUser);
return userId;
}
}

使用 Postman 测试增删改查

新增

POST http://127.0.0.1:8081/hogwartsUser/register

请求参数

{
"userName": "霍格沃兹test123",
"password": "test123"
}

响应参数

{
"id": 15,
"userName": "霍格沃兹test123",
"password": "test123",
"email": null,
"autoCreateCaseJobName": null,
"startTestJobName": null,
"defaultJenkinsId": null,
"createTime": "2021-04-14T09:37:58.358+00:00",
"updateTime": "2021-04-14T09:37:58.358+00:00"
}

查询

GET http://127.0.0.1:8081/hogwartsUser/byName?userName=霍格沃兹test123

请求参数

见请求地址中 userName =霍格沃兹test123

响应参数

[
{
"id": 15,
"userName": "霍格沃兹test123",
"password": "test123",
"email": null,
"autoCreateCaseJobName": null,
"startTestJobName": null,
"defaultJenkinsId": null,
"createTime": "2021-04-14T09:37:58.000+00:00",
"updateTime": "2021-04-14T09:37:58.000+00:00"
}
]

修改

PUT http://127.0.0.1:8081/hogwartsUser

请求参数

{
"id": 15,
"userName": "霍格沃兹test12345",
"password": "test123"
}

响应参数

{
"id": 15,
"userName": "霍格沃兹test12345",
"password": "test123",
"email": null,
"autoCreateCaseJobName": null,
"startTestJobName": null,
"defaultJenkinsId": null,
"createTime": "2021-04-14T09:43:45.018+00:00",
"updateTime": "2021-04-14T09:43:45.018+00:00"
}

删除

DELETE http://127.0.0.1:8081/hogwartsUser/15

请求参数

见请求地址中15

响应参数

15

数据持久化技术就先讲到这里啦~大家要多练习哦，才能学的更扎实。