概述

MyBatis 是一款优秀的持久层框架，它支持定制化 SQL、存储过程以及高级映射。MyBatis 避免了几乎所有的 JDBC 代码和手动设置参数以及获取结果集。 MyBatis 可以使用简单的 XML 或注解来配置和映射原生信息，将接口和 Java 的 POJOs映射成数据库中的记录。

相比Hibernate而言，MyBatis 应该算是半ORM框架，它比Hibernate更灵活，灵活在需要自己写sql语句，当然这是对于那些想自己手动写sql语句的人而言的，因为如何写好sql也是一个很重要的课题。

接下来我们就进入正题,如何整合MyBatis框架

整合MyBatis框架

在原先的demo数据库中建表sys_admin_user,并插入测试数据

SET NAMES utf8mb4;

SET FOREIGN_KEY_CHECKS = 0;

-- ----------------------------

-- Table structure for sys_admin_user

-- ----------------------------

DROP TABLE IF EXISTS `sys_admin_user`;

CREATE TABLE `sys_admin_user` (

`admin_user_id` bigint(20) NOT NULL AUTO_INCREMENT COMMENT '用户ID',

`user_name` varchar(255) CHARACTER SET utf8 COLLATE utf8_general_ci NOT NULL COMMENT '用户名',

`password` varchar(255) CHARACTER SET utf8 COLLATE utf8_general_ci NOT NULL COMMENT '密码',

`nick_name` varchar(255) CHARACTER SET utf8 COLLATE utf8_general_ci NOT NULL COMMENT '昵称',

`dept_id` bigint(20) DEFAULT NULL COMMENT '部门ID',

`phone` varchar(11) CHARACTER SET utf8 COLLATE utf8_general_ci DEFAULT NULL COMMENT '电话',

`email` varchar(50) CHARACTER SET utf8 COLLATE utf8_general_ci DEFAULT NULL COMMENT '电子邮箱',

`avatar` varchar(255) CHARACTER SET utf8 COLLATE utf8_general_ci DEFAULT NULL COMMENT '头像',

`status` tinyint(1) NOT NULL DEFAULT 1 COMMENT '状态{0:停用,1:正常}',

`deleted_flag` tinyint(1) NOT NULL DEFAULT 0 COMMENT '删除标记{0:未删,1:删除}',

`login_ip` varchar(50) CHARACTER SET utf8 COLLATE utf8_general_ci DEFAULT NULL COMMENT '最后登陆IP',

`login_time` datetime(0) DEFAULT NULL COMMENT '最后登陆时间',

`created_at` datetime(0) DEFAULT NULL COMMENT '创建时间',

`updated_at` datetime(0) DEFAULT NULL COMMENT '更新时间',

`deleted_at` datetime(0) DEFAULT NULL COMMENT '删除时间',

`created_by` bigint(20) DEFAULT 0 COMMENT '创建者ID',

`updated_by` bigint(20) DEFAULT 0 COMMENT '更新者ID',

`deleted_by` bigint(20) DEFAULT 0 COMMENT '删除者ID',

`remark` varchar(255) CHARACTER SET utf8 COLLATE utf8_general_ci DEFAULT '' COMMENT '备注',

PRIMARY KEY (`admin_user_id`) USING BTREE

) ENGINE = InnoDB AUTO_INCREMENT = 14 CHARACTER SET = utf8 COLLATE = utf8_general_ci ROW_FORMAT = Dynamic;

-- ----------------------------

-- Records of sys_admin_user

-- ----------------------------

INSERT INTO `sys_admin_user` VALUES (1, 'admin', '$2a$10$7JB720yubVSZvUI0rEqK/.VqGOZTH.ulu33dHOiBE8ByOhJIrdAu2', '卡卡罗特', 1, '123456', 'admin@qq.com', NULL, 1, 0, '127.0.0.1', '2020-10-17 16:16:11', '2020-10-17 16:16:16', '2020-10-17 16:16:18', NULL, 0, 0, 0, '超级管理');

INSERT INTO `sys_admin_user` VALUES (2, 'singlezhang', '$2a$10$7JB720yubVSZvUI0rEqK/.VqGOZTH.ulu33dHOiBE8ByOhJIrdAu2', '张三', 1, '123456', 'admin@qq.com', NULL, 1, 0, '127.0.0.1', '2020-10-17 16:16:11', '2020-10-17 16:16:16', '2020-10-17 16:16:18', NULL, 0, 0, 0, '普通管理');

INSERT INTO `sys_admin_user` VALUES (4, 'xiaoli', '$2a$10$7JB720yubVSZvUI0rEqK/.VqGOZTH.ulu33dHOiBE8ByOhJIrdAu2', '小李', 3, '123456', 'admin@qq.com', NULL, 1, 0, '127.0.0.1', '2020-10-17 16:16:11', '2020-10-17 16:16:16', '2020-10-17 16:16:18', NULL, 0, 0, 0, '普通员工');

INSERT INTO `sys_admin_user` VALUES (6, 'yiming', '$2a$10$7JB720yubVSZvUI0rEqK/.VqGOZTH.ulu33dHOiBE8ByOhJIrdAu2', '一鸣', 3, '123456', 'admin@qq.com', NULL, 1, 0, '127.0.0.1', '2020-10-17 16:16:11', '2020-10-17 16:16:16', '2020-10-17 16:16:18', NULL, 0, 0, 0, '普通员工');

INSERT INTO `sys_admin_user` VALUES (7, 'lisan', '$2a$10$7JB720yubVSZvUI0rEqK/.VqGOZTH.ulu33dHOiBE8ByOhJIrdAu2', '李三', 4, '123456', 'admin@qq.com', NULL, 1, 0, '127.0.0.1', '2020-10-17 16:16:11', '2020-10-17 16:16:16', '2020-10-17 16:16:18', NULL, 0, 0, 0, '普通员工');

INSERT INTO `sys_admin_user` VALUES (8, 'laoqian', '$2a$10$7JB720yubVSZvUI0rEqK/.VqGOZTH.ulu33dHOiBE8ByOhJIrdAu2', '老钱', 3, '123456', 'admin@qq.com', NULL, 1, 0, '127.0.0.1', '2020-10-17 16:16:11', '2020-10-17 16:16:16', '2020-10-17 16:16:18', NULL, 0, 0, 0, '普通员工');

INSERT INTO `sys_admin_user` VALUES (9, 'xiaomi', '$2a$10$7JB720yubVSZvUI0rEqK/.VqGOZTH.ulu33dHOiBE8ByOhJIrdAu2', '小米', 5, '123456', 'admin@qq.com', NULL, 1, 0, '127.0.0.1', '2020-10-17 16:16:11', '2020-10-17 16:16:16', '2020-10-17 16:16:18', NULL, 0, 0, 0, '普通员工');

INSERT INTO `sys_admin_user` VALUES (10, 'jiekema', '$2a$10$7JB720yubVSZvUI0rEqK/.VqGOZTH.ulu33dHOiBE8ByOhJIrdAu2', '杰克马', 5, '123456', 'admin@qq.com', NULL, 1, 0, '127.0.0.1', '2020-10-17 16:16:11', '2020-10-17 16:16:16', '2020-10-17 16:16:18', NULL, 0, 0, 0, '普通员工');

INSERT INTO `sys_admin_user` VALUES (11, 'misschen', '$2a$10$7JB720yubVSZvUI0rEqK/.VqGOZTH.ulu33dHOiBE8ByOhJIrdAu2', '小陈', 4, '123456', 'admin@qq.com', NULL, 1, 0, '127.0.0.1', '2020-10-17 16:16:11', '2020-10-17 16:16:16', '2020-10-17 16:16:18', NULL, 0, 0, 0, '普通员工');

INSERT INTO `sys_admin_user` VALUES (12, 'jiekema2', '$2a$10$7JB720yubVSZvUI0rEqK/.VqGOZTH.ulu33dHOiBE8ByOhJIrdAu2', '杰克马2', 3, '123456', 'admin@qq.com', NULL, 1, 0, '127.0.0.1', '2020-10-17 16:16:11', '2020-10-17 16:16:16', '2020-10-17 16:16:18', NULL, 0, 0, 0, '普通员工');

INSERT INTO `sys_admin_user` VALUES (13, 'jiekema3', '$2a$10$7JB720yubVSZvUI0rEqK/.VqGOZTH.ulu33dHOiBE8ByOhJIrdAu2', '杰克马3', 3, '123456', 'admin@qq.com', NULL, 1, 0, '127.0.0.1', '2020-10-17 16:16:11', '2020-10-17 16:16:16', '2020-10-17 16:16:18', NULL, 0, 0, 0, '普通员工');

SET FOREIGN_KEY_CHECKS = 1;

在 pom.xml中添加mybatis依赖(文中只涉及本文相关依赖,其他的依赖在前文中参考)

mysql

mysql-connector-java

org.mybatis.spring.boot

mybatis-spring-boot-starter

${mybatis.boot.version}

3.使用mybatis-generator插件生成 DAO，Model，XML映射文件,如下图:

mybatis-generator

※说明:关于mybatis-generator插件的使用，可以在《如何使用mybatis-generator插件，自动生成mybatis相关文件》一文中了解。

4.添加MyBatis配置类:MybatisConfig.java

package com.zhlab.demo.config;

import org.apache.ibatis.session.SqlSessionFactory;

import org.mybatis.spring.SqlSessionFactoryBean;

import org.mybatis.spring.annotation.MapperScan;

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

import org.springframework.context.annotation.Bean;

import org.springframework.context.annotation.Configuration;

import org.springframework.core.io.support.PathMatchingResourcePatternResolver;

import javax.sql.DataSource;

/**

* @ClassName MybatisConfig

* @Description //MybatisConfig配置类

* @Author singleZhang

* @Email 405780096@qq.com

* @Date 2020/10/31 0031 上午 9:37

**/

@Configuration

@MapperScan("com.zhlab.demo.mapper") //mapper

public class MybatisConfig {

@Autowired

private DataSource dataSource;

@Bean

public SqlSessionFactory sqlSessionFactory() throws Exception {

SqlSessionFactoryBean sessionFactory = new SqlSessionFactoryBean();

sessionFactory.setDataSource(dataSource);

sessionFactory.setTypeAliasesPackage("com.zhlab.demo.model"); // model

PathMatchingResourcePatternResolver resolver = new PathMatchingResourcePatternResolver();

sessionFactory.setMapperLocations(resolver.getResources("classpath*:mapper/*.xml")); // 扫描映射文件

return sessionFactory.getObject();

}

}

在DAO层的SysAdminUserMapper.java中添加selectAll()

package com.zhlab.demo.mapper;

import com.zhlab.demo.model.SysAdminUser;

import java.util.List;

public interface SysAdminUserMapper {

int insert(SysAdminUser record);

// 获取用户列表

List selectAll();

}

在对应的xml映射文件SysAdminUserMapper.xml中增加selectAll

select u.*

from sys_admin_user u

在service层增加SysAdminUserService.java,并调用DAO层中SysAdminUserMapper的方法

import org.springframework.stereotype.Service;

import java.util.List;

/**

* @ClassName SysAdminUserService

* @Description //TODO

* @Author singleZhang

* @Email 405780096@qq.com

* @Date 2020/10/31 0031 上午 9:45

**/

@Service

public class SysAdminUserService {

@Autowired

SysAdminUserMapper sysAdminUserMapper;

// 获取用户列表

public List findAll(){

return sysAdminUserMapper.selectAll();

}

}

在接口层创建一个UserController.java,来测试一下

package com.zhlab.demo.controller;

import com.zhlab.demo.model.SysAdminUser;

import com.zhlab.demo.service.SysAdminUserService;

import io.swagger.annotations.ApiOperation;

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

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

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

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

import java.util.List;

/**

* @ClassName UserController

* @Description //TODO

* @Author singleZhang

* @Email 405780096@qq.com

* @Date 2020/10/31 0031 上午 9:43

**/

@RestController

@RequestMapping("/user")

public class UserController {

@Autowired

SysAdminUserService sysAdminUserService;

/* 方法注解 */

@ApiOperation(value = "方法名:用户列表", notes = "获取用户列表")

@GetMapping("/list")

public List list(){

List list = sysAdminUserService.findAll();

return list;

}

}

运行这个接口,可以得到想要的所有用户的列表

用户列表

总结

Mybatis的集成还是比较简单的，后续还会讲解分页以及复杂查询，对于插件的使用可以选择一种mybatis-generator或者mybatis-plus,两种不可同时使用，会发生冲突。