SpringBoot 2.SpringBoot整合Mybatis

一、创建Springboot的配置文件：application.properties，并添加MyBatis依赖

SpringApplication 会从 application.properties 文件中加载配置信息，下面是添加Spring配置信息的文件目录顺序：

1. 当前目录下的/config子目录中
2. 当前目录中
3. 一个 classpath 包下的 /config 目录中
4. classpath 根目录中

　大家根据自己习惯来即可。

（1）application.properties 文件配置如下：

spring.datasource.driver-class-name=com.mysql.jdbc.Driver
spring.datasource.url=jdbc:mysql://127.0.0.1/test
spring.datasource.username=root
spring.datasource.password=root

（2）添加 MyBatis 以及 MYSQL

        <!-- SpringBoot - MyBatis -->
        <dependency>
            <groupId>org.mybatis.spring.boot</groupId>
            <artifactId>mybatis-spring-boot-starter</artifactId>
            <version>1.2.0</version>
        </dependency>
        <!-- Mysql -->
        <dependency>
            <groupId>mysql</groupId>
            <artifactId>mysql-connector-java</artifactId>
        </dependency>

二、创建POJO、Mapper、Service 以及 Controler

（1）User.java

package org.rcddup.app.domain;

public class User {
    private Long id;
    private String name;
    private Short age;
    private Short status;

    public Long getId() {
        return id;
    }

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

    public String getName() {
        return name;
    }

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

    public Short getAge() {
        return age;
    }

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

    public Short getStatus() {
        return status;
    }

    public void setStatus(Short status) {
        this.status = status;
    }

}

（2）UserMapper.java

package org.rcddup.app.dao;

import java.util.List;

import org.apache.ibatis.annotations.Mapper;
import org.apache.ibatis.annotations.Select;
import org.rcddup.app.domain.User;

@Mapper
public interface UserMapper {
    
    @Select("select id, name, age, status from user")
    List<User> listUser();
    
    @Select("select id, name, age, status from user where id=#{id}")
    User getUserById(Long id);
    
}

（3）IUserService.java

package org.rcddup.app.service;

import java.util.List;

import org.rcddup.app.domain.User;

public interface IUserService {
    
    List<User> listUser();
    
    User getUserById(Long id);
    
}

（4）UserService.java

package org.rcddup.app.service.impl;

import java.util.List;

import org.rcddup.app.dao.UserMapper;
import org.rcddup.app.domain.User;
import org.rcddup.app.service.IUserService;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.stereotype.Service;

@Service
public class UserService implements IUserService{
    
    @Autowired
    private UserMapper userMapper;
    
    @Override
    public List<User> listUser() {
        return userMapper.listUser();
    }

    @Override
    public User getUserById(Long id) {
        return userMapper.getUserById(id);
    }
    
}

（5）UserController.java

package org.rcddup.app.web.controller;

import java.util.List;

import org.rcddup.app.domain.User;
import org.rcddup.app.service.IUserService;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.web.bind.annotation.RequestMapping;
import org.springframework.web.bind.annotation.RestController;

@RestController
@RequestMapping("/user")
public class UserController {
    
    @Autowired
    private IUserService userService;
    
    @RequestMapping("/list")
    public List<User> list() {
        return userService.listUser();
    }
    
    @RequestMapping("/get")
    public User list(Long id) {
        return userService.getUserById(id);
    }
    
}

　　

　　重新启动 App.java

　　输入：http://localhost:8080/user/get?id=1

　　输入：http://localhost:8080/user/list

　　到此，SpringBoot整合Mybatis就成功了。

 　  因为本人比较懒，就不配置Mapper.xml了，直接使用Mybatis的注解@Select 配置查询语句。后续会讲到Mybatis逆向工程，懒人（不是本人O(∩_∩)O）所造之物，非常赞，哈哈哈！！！