目录

一 使用Spring创建Spring-web项目

1.1创建完项目如果没有Src文件夹和resources文件夹需要自己手动添加 

 1.2导入相关依赖

        1.3修改服务器端口号方法

二 LomBook用法

2.1创建实体类并添加注解(依赖在上面统一已导入)

三、Log4J日志输出

3.1：在类上添加注解

 3.2运行效果

 四 MyBatisPlus用法

        第1步：建立数据库连接

第2步：实例化UserDAO对象

        第3步：使用MyBatisPlus实现基本的CRUD

 五 MyBatis用法

5.1、在resources文件夹下创建mappers文件夹

5.2、在application.yml配置文件中配置mapper文件夹

#mybatisPlus相关配置

        mybatis-plus:

          mapper-locations: classpath:mappers/*.xml

5.3、在mapper中增删改查和登录的方法

5.4、在mappers文件夹中创建UserMapper.xml文件

5、维护方法的sql语句

5.6、在controller中测试

---

一 使用Spring创建Spring-web项目

 

 

 

1.1创建完项目如果没有Src文件夹和resources文件夹需要自己手动添加 

 

 

 1.2导入相关依赖

<!-- MyBatisPlus依赖-->
<dependency>
    <groupId>com.baomidou</groupId>
    <artifactId>mybatis-plus-boot-starter</artifactId>
    <version>3.5.1</version>
</dependency>
<!--LomBok依赖-->
<dependency>
    <groupId>org.projectlombok</groupId>
    <artifactId>lombok</artifactId> <optional>true</optional>
</dependency>
<!--mysql依赖-->
<dependency>
    <groupId>mysql</groupId>
    <artifactId>mysql-connector-java</artifactId>
    <scope>runtime</scope>
</dependency>

<!-- MyBatisPlus依赖-->
<dependency>
    <groupId>com.baomidou</groupId>
    <artifactId>mybatis-plus-boot-starter</artifactId>
    <version>3.5.1</version>
</dependency>
<!--LomBok依赖-->
<dependency>
    <groupId>org.projectlombok</groupId>
    <artifactId>lombok</artifactId> <optional>true</optional>
</dependency>
<!--mysql依赖-->
<dependency>
    <groupId>mysql</groupId>
    <artifactId>mysql-connector-java</artifactId>
    <scope>runtime</scope>
</dependency>

1.3修改服务器端口号方法

注意:文件名必须是application.yml

端口号自己可以随意设置

 

 

二 LomBook用法

2.1创建实体类并添加注解(依赖在上面统一已导入)

 

三、Log4J日志输出

3.1：在类上添加注解

 

 3.2运行效果

 

 四 MyBatisPlus用法

第1步：建立数据库连接

 

# 配置数据源信息
  datasource:
    # 配置数据源类型
    type: com.zaxxer.hikari.HikariDataSource
    # 配置连接数据库信息
    driver-class-name: com.mysql.cj.jdbc.Driver
    url: jdbc:mysql://localhost:3306/text?characterEncoding=utf-8&useSSL=false
    username: 
    password: 

第2步：实例化UserDAO对象

@Autowired(required=false)
private UserMapper mapper;

第3步：使用MyBatisPlus实现基本的CRUD

   /**
     * 新增
     * @return
     */
    @RequestMapping("/hello3")
    public int insert(){
        User user = new User(null,"admin","password");
        int count = dao.insert(user);
        return count;
    }

    /**
     * 查询所有
     * @return
     */
    @RequestMapping("/hello4")
    public List<User> selectList(){
        List<User> list = dao.selectList(null);
        return list;
    }

    /**
     * 根据id查询
     * @return
     */
    @RequestMapping("/hello5")
    public User selectById(){
        User user = dao.selectById(1592407936371752962L);
        return user;

    }

    /**
     * 根据id修改(需要创建一个要修改的对象)
     * @return
     */
    @RequestMapping("/hello6")
    public int updateId(){
        int count = dao.updateById(new User(1592407936371752962L, "tom", "666"));
        return count;
    }

    /**
     * 根据id删除
     * @return
     */
    @RequestMapping("/hello7")
    public int deleteId(){
        int count = dao.deleteById(1101L);
        return count;

    }

    /**
     * 根据id删除多调数据,使用Arrays.asList(数组转集合) myBatisPlus
     * @return
     */
    @RequestMapping("/hello8")
    public  int deleteIdS(){
        int count = dao.deleteBatchIds(Arrays.asList(1592407936371752962L,1592421019714490370L,1592421018984681474L,1592421018284232705L));
        return count;

 五 MyBatis用法

5.1、在resources文件夹下创建mappers文件夹

5.2、在application.yml配置文件中配置mapper文件夹

#mybatisPlus相关配置
mybatis-plus:
  mapper-locations: classpath:mappers/*.xml

5.3、在mapper中增删改查和登录的方法

 

5.4、在mappers文件夹中创建UserMapper.xml文件

 

通过namespace指定DAO接口的路径

<?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="demo.dao.UserDAO">

</mapper>

5、维护方法的sql语句

<mapper namespace="demo.dao.UserDAO">
    <select id="login" resultType="demo.entity.User">
        select * from t_user where user_name=#{userName} and password=#{password}
    </select>

    <insert id="addUser">
        insert into t_user values(#{id},#{userName},#{password})
    </insert>

    <delete id="deleteById">
        delete from t_user where id=#{id}
    </delete>

    <update id="updateUser">
        update t_user  set user_name=#{userName},password=#{password} where id=#{id}
    </update>
</mapper>

 

<select id="login" resultType="demo.entity.User">
    select * from t_user where user_name=#{userName} and password=#{password}
</select>

<insert id="addUser">
    insert into t_user values(#{id},#{userName},#{password})
</insert>

<delete id="deleteById">
    delete from t_user where id=#{id}
</delete>

<update id="updateUser">
    update t_user  set user_name=#{userName},password=#{password} where id=#{id}
</update>

5.6、在controller中测试

/**
     * 登录
     * @param userName
     * @param password
     * @return
     */
    @RequestMapping(("/login"))
    public String login(String userName,String password){
        User u = dao.login(userName, password);
        if(u!=null){
            return  "登录成功";
        }else{
            return  "登录失败";
        }
    }

    /**
     * 使用myBatis增加
     * @return
     */
    @RequestMapping("/hello9")
    public  int addUser(){
        User user = new User(111L,"admin","1234");
        int count = dao.addUser(user);
        return count;
    }

    /**
     * 删除
     * @return
     */
    @RequestMapping("hello10")
    public int deleteById(){
        int count = dao.deleteById(1592421006250774530L);
        return count;
    }

    /**
     * 查询
     * @return
     */
    @RequestMapping("/hello11")
    public int updateById(){
        User user = new User(1592421016656842753L,"aaa","333");
        int count = dao.updateUser(user);
        return count;
    }
}