SpringBoot整合Mybatis-plus的具体过程使用

2024-02-27 18:30:03

1.MyBatisX插件

在使用mybatis或者mybatis-plus时,我们可以安装IDEA的MyBatis的插件 - MyBatisX,

这样我们就可以实现点击接口跳转到sql文件, 点击sql文件可以跳转到接口的功能, 很方便.这个插件的功能还有很多, 可以查看MyBatis-Plus官网

安装方法：打开 IDEA，进入 File -> Settings -> Plugins -> Browse Repositories，输入 mybatisx 搜索并安装, 然后重启IDEA。

点击小鸟可实现跳转

2.引入依赖

在pom.xml添加如下依赖

 <!--数据库相关-->
        <dependency>
            <groupId>com.baomidou</groupId>
            <artifactId>mybatis-plus-boot-starter</artifactId>
            <version>3.4.1</version>
        </dependency>
        <dependency>
            <groupId>mysql</groupId>
            <artifactId>mysql-connector-java</artifactId>
            <version>5.1.6</version>
        </dependency>
        <dependency>
            <groupId>com.alibaba</groupId>
            <artifactId>druid-spring-boot-starter</artifactId>
            <version>1.1.17</version>
        </dependency>

3.编写配置

application.properties

server.port=8080
spring.datasource.url=jdbc:mysql://localhost:3306/db_springtest?useUnicode=true&characterEncoding=utf8
spring.datasource.username=root
spring.datasource.password=123456
spring.datasource.driver-class-name=com.mysql.jdbc.Driver

#----------------------------配置mybatis-plus---------------------------
#配置sql文件路径
mybatis-plus.mapper-locations=classpath:/mapper/*.xml
#开启驼峰命名映射
mybatis-plus.configuration.map-underscore-to-camel-case=true
## 自定义sql中表名带前缀, 默认是实体名的小写, 如user, 但是数据库中是t_user, 所以设置加上前缀
mybatis-plus.global-config.db-config.table-prefix=t_

#----------------------------配置druid--------------------------------
#监控SpringBean
spring.datasource.druid.aop-patterns=com.limi.springboottest2.*
# 底层开启功能，stat（sql监控），wall（防火墙）
spring.datasource.druid.filters=stat,wall

# 配置监控页功能
spring.datasource.druid.stat-view-servlet.enabled=true
spring.datasource.druid.stat-view-servlet.login-username=admin
spring.datasource.druid.stat-view-servlet.login-password=123456
spring.datasource.druid.stat-view-servlet.reset-enable=false

# 监控web
spring.datasource.druid.web-stat-filter.enabled=true
spring.datasource.druid.web-stat-filter.url-pattern=/*
spring.datasource.druid.web-stat-filter.exclusions='*.js,*.gif,*.jpg,*.png,*.css,*.ico,/druid/*'

# 对上面filters里面的stat的详细配置
spring.datasource.druid.filter.stat.slow-sql-millis=1000
spring.datasource.druid.filter.stat.log-slow-sql=true
spring.datasource.druid.filter.stat.enabled=true
spring.datasource.druid.filter.wall.enabled=true
spring.datasource.druid.filter.wall.config.drop-table-allow=false

4.编写接口

UserMapper

package com.limi.springboottest2.mapper;
import com.baomidou.mybatisplus.core.mapper.BaseMapper;
import com.limi.springboottest2.entity.User;
import org.springframework.stereotype.Repository;
@Repository
public interface UserMapper extends BaseMapper<User> {
    User getUserById(Integer id);
}

UserMapper.xml

<?xml version="1.0" encoding="UTF-8" ?>
<!DOCTYPE mapper
        PUBLIC "-//mybatis.org//DTD Mapper 3.0//EN"
        "http://mybatis.org/dtd/mybatis-3-mapper.dtd">
<!--
        namespace：必须有值，自定义的唯一字符串
        推荐使用：dao 接口的全限定名称 -->
<mapper namespace="com.limi.springboottest2.mapper.UserMapper">
    <select id="getUserById" resultType="com.limi.springboottest2.entity.User">
        select * from t_user where id = #{id}
    </select>
</mapper>

注意要开启mapper接口文件的扫描

SpringbootTest2Application

package com.limi.springboottest2;
import org.mybatis.spring.annotation.MapperScan;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.boot.SpringApplication;
import org.springframework.boot.autoconfigure.SpringBootApplication;
import org.springframework.context.ConfigurableApplicationContext;
@SpringBootApplication
@MapperScan("com.limi.springboottest2.mapper")//扫描mapper
public class SpringbootTest2Application {
    public static void main(String[] args) {
        //1、返回我们IOC容器
        ConfigurableApplicationContext run = SpringApplication.run(SpringbootTest2Application.class, args);
    }
}

5.运行测试

HelloController

package com.limi.springboottest2.controller;
import com.limi.springboottest2.entity.User;
import com.limi.springboottest2.mapper.UserMapper;
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.ResponseBody;
import java.util.List;
@Controller
public class HelloController {
    @Autowired
    private UserMapper userMapper;
    //测试自己编写sql语句的查询方法
    @ResponseBody
    @GetMapping("/getUser/{id}")
    public User test1(@PathVariable("id") Integer id){
        User user = userMapper.getUserById(id);
        return user;
    }
    //测试mybatis-plus内置的查询方法
    @ResponseBody
    @GetMapping("/getAllUser")
    public List<User> test2(){
        List<User> userList = userMapper.selectList(null);//查询所有
        return userList;
    }
}

6.完整代码

pom.xml

<?xml version="1.0" encoding="UTF-8"?>
<project xmlns="http://maven.apache.org/POM/4.0.0" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
         xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 https://maven.apache.org/xsd/maven-4.0.0.xsd">
    <modelVersion>4.0.0</modelVersion>
    <parent>
        <groupId>org.springframework.boot</groupId>
        <artifactId>spring-boot-starter-parent</artifactId>
        <version>2.7.0</version>
        <relativePath/> <!-- lookup parent from repository -->
    </parent>
    <groupId>com.limi</groupId>
    <artifactId>springboot-test2</artifactId>
    <version>0.0.1-SNAPSHOT</version>
    <name>springboot-test2</name>
    <description>Demo project for Spring Boot</description>
    <properties>
        <java.version>1.8</java.version>
    </properties>
    <dependencies>
        <dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-starter-web</artifactId>
        </dependency>
        <dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-devtools</artifactId>
            <scope>runtime</scope>
            <optional>true</optional>
        </dependency>
        <dependency>
            <groupId>org.projectlombok</groupId>
            <artifactId>lombok</artifactId>
            <optional>true</optional>
        </dependency>
        <dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-starter-test</artifactId>
            <scope>test</scope>
        </dependency>
        <dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-configuration-processor</artifactId>
            <optional>true</optional>
        </dependency>
        <!--数据库相关-->
        <dependency>
            <groupId>com.baomidou</groupId>
            <artifactId>mybatis-plus-boot-starter</artifactId>
            <version>3.4.1</version>
        </dependency>
        <dependency>
            <groupId>mysql</groupId>
            <artifactId>mysql-connector-java</artifactId>
            <version>5.1.6</version>
        </dependency>
        <dependency>
            <groupId>com.alibaba</groupId>
            <artifactId>druid-spring-boot-starter</artifactId>
            <version>1.1.17</version>
        </dependency>
    </dependencies>
    <build>
        <plugins>
            <plugin>
                <groupId>org.springframework.boot</groupId>
                <artifactId>spring-boot-maven-plugin</artifactId>
                <configuration>
                    <excludes>
                        <exclude>
                            <groupId>org.projectlombok</groupId>
                            <artifactId>lombok</artifactId>
                        </exclude>
                    </excludes>
                </configuration>
            </plugin>
            <!-- 下面插件作用是工程打包时，不将spring-boot-configuration-processor打进包内，让其只在编码的时候有用 -->
            <plugin>
                <groupId>org.springframework.boot</groupId>
                <artifactId>spring-boot-maven-plugin</artifactId>
                <configuration>
                    <excludes>
                        <exclude>
                            <groupId>org.springframework.boot</groupId>
                            <artifactId>spring-boot-configuration-processor</artifactId>
                        </exclude>
                    </excludes>
                </configuration>
            </plugin>
        </plugins>
    </build>
</project>