CREATE TABLE IF NOT EXISTS user (
 `id` INT(10) NOT NULL AUTO_INCREMENT,
 `name` VARCHAR(50) NULL DEFAULT NULL ,
 `age` INT(2) NOT NULL ,
 PRIMARY KEY (id)
)

<parent>
  <groupId>org.springframework.boot</groupId>
  <artifactId>spring-boot-starter-parent</artifactId>
  <version>1.4.2.RELEASE</version>
  <relativePath />
</parent>

<dependencies>
  <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</artifactId>
    <version>1.1.1</version>
  </dependency>
  <dependency>
    <groupId>mysql</groupId>
    <artifactId>mysql-connector-java</artifactId>
    <version>5.1.40</version>
  </dependency>
</dependencies>

<build>
  <plugins>
    <plugin>
      <groupId>org.springframework.boot</groupId>
      <artifactId>spring-boot-maven-plugin</artifactId>
    </plugin>
  </plugins>
</build>

spring.datasource.driver-class-name=com.mysql.jdbc.Driver
spring.datasource.url=jdbc:mysql://localhost:3306/test?useSSL=false&useUnicode=true&characterEncoding=UTF-8
spring.datasource.username=root
spring.datasource.password=123456

package com.xyz.dbtest.entity;
public class User {
  private int id;
  private String name;
  private int age;

  public int getId() {  return id;  }

  public void setId(int id) { this.id = id;  }

  public String getName() {  return name;  }

  public void setName(String name) { this.name = name;  }

  public int getAge() {  return age;  }

  public void setAge(int age) {  this.age = age;  }
}

package com.xyz.dbtest.dao;

import com.xyz.dbtest.entity.User;
import org.apache.ibatis.annotations.Mapper;
import org.apache.ibatis.annotations.Result;
import org.apache.ibatis.annotations.Results;
import org.apache.ibatis.annotations.Select;
import java.util.List;

@Mapper //1
public interface UserDao {
  @Results({ //2
      @Result(property = "id", column = "id"), //2
      @Result(property = "name", column = "name"),
      @Result(property = "age", column = "age")
  })
  @Select("SELECT * FROM user WHERE age = #{age}") //3
  List<User> get(int age);

  @Insert("INSERT INTO user(name, age) VALUES (#{name}, #{age})") //3
  void insert(User user);
}

package com.xyz.dbtest.service;

import com.xyz.dbtest.dao.UserDao;
import com.xyz.dbtest.entity.User;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.stereotype.Service;
import java.util.List;

@Service //声明成一个spring bean
public class UserService {

  @Autowired //连接到UserDao Bean
  private UserDao userDao;

  public String show() {
    return "Hello World!";
  }

  public List<User> showDao(int age) {
    return userDao.get(age);
  }

  public String insert(String name, int age) { //插入一条记录
    User user = new User();
    user.setName(name);
    user.setAge(age);
    userDao.insert(user);
    return "Insert ( \""+name+"\", age"+age+") OK!";
  }
}

package com.xyz.dbtest.controller;

import com.xyz.dbtest.service.UserService;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.web.bind.annotation.RequestMapping;
import org.springframework.web.bind.annotation.ResponseBody;
import org.springframework.web.bind.annotation.RestController;

@RestController //声明为一个Restful的Controller
public class UserController {
  @Autowired //自动连接到UserService Bean
  private UserService userService;

  @RequestMapping(value = "/show")
  public String show() {
    return userService.show();
  }

  @RequestMapping(value = "/showDao")
  public Object showDao(int age) {
    return userService.showDao(age);
  }

  @RequestMapping(value="/insert")
  public String insert(String name, int age) {
    return userService.insert(name, age);
  }
}

package com.xyz.dbtest.main;

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

@SpringBootApplication(scanBasePackages = "com.xyz.dbtest") //1
@MapperScan(basePackages = "com.xyz.dbtest.dao") //2
public class StartApp {
  public static void main(String[] args) {
    SpringApplication.run(StartApp.class, args);
  }
}