父pom文件

<?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>3.1.2</version>--><version>2.2.5.RELEASE</version><relativePath/> <!-- lookup parent from repository --></parent><groupId>com.chensir</groupId><artifactId>springboot</artifactId><version>0.0.1-SNAPSHOT</version><name>springboot</name><description>springboot</description><properties><java.version>8</java.version><hutool.version>5.8.3</hutool.version><lombok.version>1.18.24</lombok.version><alibaba-sdk.version>2.0.0</alibaba-sdk.version></properties><packaging>pom</packaging><modules><module>servlet</module><module>spring-interceptor</module><module>spring-aop</module><module>spring-united-reslut</module><module>spring-jdbc</module><module>spring-mybatis</module></modules><dependencyManagement><dependencies><!--钉钉机器人消息--><dependency><groupId>com.aliyun</groupId><artifactId>alibaba-dingtalk-service-sdk</artifactId><version>${alibaba-sdk.version}</version></dependency><dependency><groupId>cn.hutool</groupId><artifactId>hutool-all</artifactId><version>${hutool.version}</version></dependency><dependency><groupId>org.projectlombok</groupId><artifactId>lombok</artifactId><version>${lombok.version}</version></dependency>
<!--父pom中不要加此依赖，否则依赖clean会报错，原因是父pom中并没指定版本-->
<!--            <dependency>-->
<!--                <groupId>org.springframework.boot</groupId>-->
<!--                <artifactId>spring-boot-starter-web</artifactId>-->
<!--            </dependency>--><!--            <dependency>-->
<!--                <groupId>org.springframework.boot</groupId>-->
<!--                <artifactId>spring-boot-starter-test</artifactId>-->
<!--                <scope>test</scope>-->
<!--            </dependency>--></dependencies></dependencyManagement><build><plugins><plugin><groupId>org.springframework.boot</groupId><artifactId>spring-boot-maven-plugin</artifactId></plugin></plugins></build></project>

pom文件

<?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>com.chensir</groupId><artifactId>springboot</artifactId><version>0.0.1-SNAPSHOT</version><relativePath>../pom.xml</relativePath></parent><artifactId>spring-mybatis</artifactId><dependencies><dependency><groupId>com.github.pagehelper</groupId><artifactId>pagehelper</artifactId><version>5.1.10</version></dependency><dependency><groupId>org.mybatis.spring.boot</groupId><artifactId>mybatis-spring-boot-starter</artifactId><version>2.1.4</version></dependency><dependency><groupId>mysql</groupId><artifactId>mysql-connector-java</artifactId><scope>runtime</scope></dependency><dependency><groupId>cn.hutool</groupId><artifactId>hutool-all</artifactId></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-starter-web</artifactId></dependency><dependency><groupId>org.mybatis.spring.boot</groupId><artifactId>mybatis-spring-boot-starter-test</artifactId><version>2.1.4</version><scope>test</scope></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></plugins></build></project>

配置文件


spring.datasource.url=jdbc:mysql://localhost/db1?useUnicode=true&characterEncoding=utf8&zeroDateTimeBehavior=convertToNull&useSSL=true&serverTimezone=GMT%2B8&autoReconnect=true&rewriteBatchedStatements=true
spring.datasource.username=root
spring.datasource.password=root
spring.datasource.driver-class-name=com.mysql.cj.jdbc.Driver

MyResponseBodyAdvice

package com.chensir.advice;import cn.hutool.core.lang.Dict;
import cn.hutool.core.util.StrUtil;
import cn.hutool.json.JSONUtil;
import com.github.pagehelper.Page;
import org.springframework.core.MethodParameter;
import org.springframework.http.MediaType;
import org.springframework.http.converter.StringHttpMessageConverter;
import org.springframework.http.server.ServerHttpRequest;
import org.springframework.http.server.ServerHttpResponse;
import org.springframework.web.bind.annotation.ExceptionHandler;
import org.springframework.web.bind.annotation.RestControllerAdvice;
import org.springframework.web.servlet.mvc.method.annotation.ResponseBodyAdvice;import javax.servlet.http.HttpServletRequest;// 拦截范围为 com.chensir.controller包下内容
@RestControllerAdvice(basePackages = {"com.chensir.controller"})
public class MyResponseBodyAdvice implements ResponseBodyAdvice {// 是否开启拦截 true开启 false不开启@Overridepublic boolean supports(MethodParameter methodParameter, Class aClass) {// 此处应该改为true,否则除了异常外 走到此处为false后就直接返回,也不再继续往下走了！return true;}// 如果接口返回异常就在此处拦截 进行封装;value = Exception.class 对所有的异常均拦截！@ExceptionHandler(value = Exception.class)public Object defaultErrorHandler(HttpServletRequest req, Exception ex){ResponseDto<Object> responseDto = new ResponseDto<>();responseDto.setCode(501);responseDto.setMessage(ex.getMessage());return responseDto;}@Overridepublic Object beforeBodyWrite(Object body, MethodParameter methodParameter, MediaType mediaType, Class aClass, ServerHttpRequest serverHttpRequest, ServerHttpResponse serverHttpResponse) {// 有的接口再返回时会自己封装code,message,data。如果body是ResponseDto类型的实例，那么就直接返回body
//        if(body instanceof ResponseDto){
//            return body;
//        }ResponseDto<Object> responseDto = new ResponseDto<>();// 先用hutool定义为nullString message = StrUtil.EMPTY;responseDto.setCode(0);responseDto.setMessage(message);if (body instanceof Page){Page page = (Page) body;int pages = page.getPages();//总页数long total = page.getTotal();//总条数Dict dict = Dict.create().set("total",total).set("pages",pages).set("item",body);responseDto.setData(dict);}else {responseDto.setData(body);}// 如果是string类型就用json封装一下;if (aClass == StringHttpMessageConverter.class) {return JSONUtil.toJsonStr(responseDto);} else {return responseDto;}}
}

ResponseDto<T>

package com.chensir.advice;import lombok.Data;import java.io.Serializable;// 泛型
@Data
public class ResponseDto<T> implements Serializable {// 返回码(内部拟定)private int code;// 返回信息private String message;private T data;
}

MyBatisConfig

package com.chensir.config;import com.github.pagehelper.PageInterceptor;
import lombok.extern.slf4j.Slf4j;
import org.apache.ibatis.session.SqlSessionFactory;
import org.mybatis.spring.SqlSessionFactoryBean;
import org.mybatis.spring.boot.autoconfigure.ConfigurationCustomizer;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.context.annotation.Bean;
import org.springframework.context.annotation.Configuration;
import org.springframework.core.io.Resource;
import org.springframework.core.io.support.PathMatchingResourcePatternResolver;
import org.springframework.core.io.support.ResourcePatternResolver;
import org.springframework.util.CollectionUtils;import javax.sql.DataSource;
import java.io.IOException;
import java.util.ArrayList;
import java.util.Arrays;
import java.util.List;@Configuration
@Slf4j
public class MyBatisConfig {@Autowiredprivate ConfigurationCustomizer configurationCustomizer;/*** 自己注册SqlSessionFactory 目的是增强功能，添加分页插件* @param ds 代表数据源* @return* @throws Exception*/@Beanpublic SqlSessionFactory sqlSessionFactory(DataSource ds) throws Exception {SqlSessionFactoryBean factoryBean = new SqlSessionFactoryBean();// 设置数据源factoryBean.setDataSource(ds);// 把分页插件设置到SqlSessionFactory插件库factoryBean.setPlugins(new PageInterceptor());// 配置mapper.xml地址factoryBean.setMapperLocations(resolveMapperLocations());//驼峰映射注册到SqlSessionFactory中org.apache.ibatis.session.Configuration configuration = new org.apache.ibatis.session.Configuration();configurationCustomizer.customize(configuration);factoryBean.setConfiguration(configuration);// 返回具体实例对象SqlSessionFactory bean = factoryBean.getObject();return bean;}/*** 开启驼峰映射* @return*/@Beanpublic ConfigurationCustomizer configurationCustomizer(){return new ConfigurationCustomizer() {@Overridepublic void customize(org.apache.ibatis.session.Configuration configuration) {configuration.setMapUnderscoreToCamelCase(true);}};}/*** 查找 xxxMapper.xml* @return*/public Resource[] resolveMapperLocations() {ResourcePatternResolver resourceResolver = new PathMatchingResourcePatternResolver();List<String> mapperLocations = new ArrayList<>();mapperLocations.add("classpath*:mapper/*Mapper.xml");
//        mapperLocations.add("classpath*:com/meiwei/ping/dao/**/*Mapper.xml");List<Resource> resources = new ArrayList();if (!CollectionUtils.isEmpty(mapperLocations)) {for (String mapperLocation : mapperLocations) {try {Resource[] mappers = resourceResolver.getResources(mapperLocation);resources.addAll(Arrays.asList(mappers));} catch (IOException e) {log.error("Get myBatis resources happened exception", e);}}}return resources.toArray(new Resource[resources.size()]);}}

UsersController

package com.chensir.controller;import com.chensir.entity.Users;
import com.chensir.service.UsersService;
import com.github.pagehelper.Page;
import com.github.pagehelper.PageHelper;
import com.github.pagehelper.PageInfo;
import org.springframework.web.bind.annotation.GetMapping;
import org.springframework.web.bind.annotation.RestController;import javax.annotation.Resource;
import java.util.HashMap;
import java.util.List;
import java.util.Map;@RestController
public class UsersController {@Resourceprivate UsersService usersService;@GetMapping("/demo1")public List selectUsersList(Integer pageNum,Integer pageSize) {// 启用分页，查询第一页，每页3条PageHelper.startPage(pageNum,pageSize);//-------------PageInfo方式---------------
//        PageInfo<Users> usersPageInfo = new PageInfo<>(usersService.selectUsersList());
//        return usersPageInfo;//-------------PageInfo方式---------------//-------------Page方式---------------
//        List<Users> users = usersService.selectUsersList();
//        Page page = (Page) users;
//        int pages = page.getPages();
//        long total = page.getTotal();
//
//
//        Map<String,Object> pageMap = new HashMap<>();
//        pageMap.put("pages",pages);
//        pageMap.put("total",total);
//        pageMap.put("items",users);
//        return pageMap;//-------------Page方式---------------//-----------使用ResponseBodyAdvice------------List<Users> users = usersService.selectUsersList();return users;//-----------使用ResponseBodyAdvice------------}@GetMapping("/demo2")public Users selectUsers(){Users users = usersService.selectUsers();return users;}@GetMapping("/demo3")public Map selectUsersToMap(){return usersService.selectUsersToMap();}
}

UsersMapper

@Mapper
public interface UsersMapper {List<Users> selectUsersList();Users selectUsers();Map<String,Object> selectUsersToMap();
}

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">
<mapper namespace="com.chensir.mapper.UsersMapper"><select id="selectUsersList" resultType="com.chensir.entity.Users">select * from users</select><select id="selectUsers" resultType="com.chensir.entity.Users">select * from users where id = 1</select><select id="selectUsersToMap" resultType="java.util.Map">select * from users where id = 1</select>
</mapper>

结果

{"code": 0,"message": "","data": {"total": 5,"pages": 2,"item": [{"id": 1,"name": "chjnzkcn","age": 18,"sex": "男","tel": "123","createTime": "2023-05-11","updateTime": "2023-05-11"},{"id": 2,"name": "czvfzsvdv","age": 20,"sex": "男","tel": "2315","createTime": "2023-05-11","updateTime": "2023-05-11"},{"id": 3,"name": "sczvszv","age": 18,"sex": "女","tel": "2112321","createTime": "2023-05-11","updateTime": "2023-05-11"}]}
}