添加pom支持

<!--Mybatis-->
        <dependency>
            <groupId>org.mybatis.spring.boot</groupId>
            <artifactId>mybatis-spring-boot-starter</artifactId>
            <version>1.0.0</version>
        </dependency>

定义SysUserMapper.xml，默认地址 src/main/resources

<?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.duck.dao.SysUserMapper" >

    <resultMap id="SysUserMap" type="com.duck.bean.SysUser" >
        <id column="id" property="id"/>
        <result column="real_name" property="realName"/>
        <result column="login_name" property="loginName"/>
        <result column="password" property="password"/>
    </resultMap>
    

    <select id="querySysUser" parameterType="java.util.Map" resultMap="SysUserMap">
        select * from sys_user
    </select>
    
</mapper>

定义dao,SysUserMapper

package com.duck.dao;

import com.duck.bean.SysUser;

import java.util.List;
import java.util.Map;

public interface SysUserMapper {

    List<SysUser> querySysUser(Map param);

}

SysUserServiceImpl注入添加方法

package com.duck.service;

import com.duck.bean.SysUser;
import com.duck.dao.SysUserMapper;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.jdbc.core.JdbcTemplate;
import org.springframework.jdbc.core.RowMapper;
import org.springframework.stereotype.Service;

import java.sql.ResultSet;
import java.sql.SQLException;
import java.util.List;
import java.util.Map;

@Service
public class SysUserServiceImpl implements SysUserService{

    @Autowired
    JdbcTemplate jdbcTemplate;

    @Autowired
    SysUserMapper sysUserDao;

    //使用JdbcTemplate访问
    public List<SysUser> querySysUser(Map map){
        String sql = "select * from sys_user ";
        return jdbcTemplate.query(sql, new RowMapper<SysUser>() {
            @Override
            public SysUser mapRow(ResultSet resultSet, int i) throws SQLException {
                SysUser sysUser = new SysUser();
                sysUser.setId(resultSet.getInt("id"));
                sysUser.setLoginName(resultSet.getString("login_name"));
                sysUser.setRealName(resultSet.getString("real_name"));
                sysUser.setPassword(resultSet.getString("password"));
                return sysUser;
            }
        });
    }

    //使用mybatis访问
    public List<SysUser> qrySysUser(Map map){
        List<SysUser> sysUserList = sysUserDao.querySysUser(map);
        return sysUserList;
    }

}

SysUserService接口添加方法

package com.duck.service;

import com.duck.bean.SysUser;

import java.util.List;
import java.util.Map;

public interface SysUserService {

    List<SysUser> querySysUser(Map map);

    List<SysUser> qrySysUser(Map map);
}

DuckController添加访问方法

package com.duck.controller;

import com.duck.bean.SysUser;
import com.duck.service.SysUserService;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.beans.factory.annotation.Value;
import org.springframework.stereotype.Controller;
import org.springframework.web.bind.annotation.RequestMapping;
import org.springframework.web.bind.annotation.ResponseBody;

import java.util.HashMap;
import java.util.List;
import java.util.Map;

//会返回jsp界面
@Controller
//RestController是Controller 与 ResponseBody的合体，返回的是json字符串
//@RestController
public class DuckController {

    private static final Logger logger = LoggerFactory.getLogger(DuckController.class);

    //取配置文件配置的参数（如果配置文件没有配置appplication.hello 那就取冒号后的值）
    @Value("${application.hello:配置是空取我}")
    private String hello = "";

    @Autowired
    SysUserService sysUserService;

    @RequestMapping("/index")
    public String index(Map<String, Object> model){
        logger.info("index方法");
        model.put("hello",hello);
        model.put("message","SpringBoot项目的首页");
        //返回字符串，框架会默认去目录spring.mvc.view.prefix定义的文件夹下找(字符串+spring,mvc.view.suffix)的jsp文件
        return "index";
    }

    @RequestMapping("/freemarker")
    public String freemarker(Map<String,Object> model){
        logger.info("freemarker方法");
        model.put("message","freemarker首页");
        return "freemarker";
    }

    @RequestMapping("querySysUser")
    public @ResponseBody List<SysUser> querySysUser(){
        logger.info("JdbcTemplate 查询用户");
        List<SysUser> sysUserList = sysUserService.querySysUser(new HashMap());
        return sysUserList;
    }

    @RequestMapping("qrySysUser")
    public @ResponseBody List<SysUser> qrySysUser(){
        logger.info("Mybatis 查询用户");
        List<SysUser> sysUserList = sysUserService.qrySysUser(new HashMap());
        return sysUserList;
    }
}

配置文件添加Mybatis实体类与xml文件路径

#Mybatis的实体与配置文件位置  mapperLocations的默认位置是src/main/resources
mybatis.typeAliasesPackage=com.duck.bean
mybatis.mapperLocations=classpath:xml/*Mapper.xml

启动类添加MapperScan，扫描dao

package com.duck;

import com.duck.servlet.DuckTestServlet;
import org.mybatis.spring.annotation.MapperScan;
import org.springframework.boot.SpringApplication;
import org.springframework.boot.autoconfigure.SpringBootApplication;
import org.springframework.boot.web.servlet.ServletComponentScan;
import org.springframework.boot.web.servlet.ServletRegistrationBean;
import org.springframework.context.annotation.Bean;

@SpringBootApplication(scanBasePackages = {"com.duck"},exclude={})
//扫描工程中的Servlet Listener Filter
@ServletComponentScan(basePackages = {"com.duck"})
//mybatis框架中的dao扫描
@MapperScan("com.duck.dao")
public class DuckAdminApplication {

    public static void main(String[] args) {
        SpringApplication.run(DuckAdminApplication.class, args);
    }

    /**
     * 通过代码的形式注册一个Servlet，这种形式不需要添加@ServletComponentScan注解来扫描
     * @return
     */
    @Bean
    public ServletRegistrationBean servletRegistrationBean() {
        return new ServletRegistrationBean(new DuckTestServlet(), "/duckTest/*");
    }

}

访问路径 可得查询结果，是通过mybatis查询获取

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