1.配置mybatis-config.xml

在资源目录resources中创建mybatis-config.xml文件，并引入dtd约束

<?xml version="1.0" encoding="UTF-8" ?>
<!DOCTYPE configuration
       PUBLIC "-//mybatis.org//DTD Config 3.0//EN"
       "http://mybatis.org/dtd/mybatis-3-config.dtd">
<configuration>

</configuration>

2.数据配置文件database.properties

jdbc.driver=com.mysql.jdbc.Driver
jdbc.url=jdbc:mysql://localhost:3306/ssm-test?useSSL=true&useUnicode=true&characterEncoding=utf8
jdbc.username=root
jdbc.password=123456

3.IDEA关联mysql数据库

IDEA关联MySQL数据库_w506667090的博客-CSDN博客

4.编写数据库对应的实体类

并使用lombok自动生成getter&setter方法和有参无参构造器，前提是IDEA中添加了lombok插件，如果没有可以下载lombok插件或手动生成相关方法。

package com.wanjl.pojo;

import lombok.AllArgsConstructor;
import lombok.Data;
import lombok.NoArgsConstructor;
/**
    @Data   注在类上，提供类的get、set、equals、hashCode、canEqual、toString方法
    @AllArgsConstructor  注在类上，提供类的全参构造
    @NoArgsConstructor  注在类上，提供类的无参构造
 */
@Data
@AllArgsConstructor
@NoArgsConstructor
public class Books {
    private int bookID;
    private String bookName;
    private int bookCounts;
    private String detail;
}

5.编写dao层的mapper接口

package com.wanjl.dao;

import com.wanjl.pojo.Books;

import java.util.List;

public interface BookMapper {
    //添加图书
    int addBook(Books books);
    //修改图书
    int updateBook(Books books);
    //删除图书
    int deleteBookById(int id);
    //查询一本图书
    Books queryBookById(int id);
    //查询所有图书
    List<Books> queryAllBook();
}

6.编写接口对于的mapper.xml文件

需要导入mybatis的包

<?xml version="1.0" encoding="UTF-8" ?>
<!DOCTYPE mapper
        PUBLIC "-//mybatis.org//DTD Config 3.0//EN"
        "http://mybatis.org/dtd/mybatis-3-mapper.dtd">

<mapper namespace="com.wanjl.dao.BookMapper">
    <!--添加图书-->
    <insert id="addBook" parameterType="Books">
        insert into `ssm-test`.books(bookName, bookCounts, detail)
        values (${bookName},${bookCounts},${detail});
    </insert>
    <!--修改图书-->
    <update id="updateBook" parameterType="Books">
        update `ssm-test`.books
        set bookName=${bookName},bookCounts=${bookCounts},detail=${detail}
        where bookID=${bookID};
    </update>
    <!--删除图书-->
    <delete id="deleteBookById" parameterType="int">
        delete from `ssm-test`.books
        where bookID=${bookID};
    </delete>
    <!--查询一本图书-->
    <select id="queryBookById" resultType="Books">
        select *
        from `ssm-test`.books
        where bookID=${bookID};
    </select>
    <!--查询所有图书信息-->
    <select id="queryAllBook" resultType="Books">
        select *
        from `ssm-test`.books;
    </select>
</mapper>

7.编写mybatis核心配置文件

<?xml version="1.0" encoding="UTF-8" ?>
<!DOCTYPE configuration
        PUBLIC "-//mybatis.org//DTD Config 3.0//EN"
        "http://mybatis.org/dtd/mybatis-3-config.dtd">
<configuration>
    <typeAliases>
        <package name="com.wanjl.pojo"/>
    </typeAliases>
    <mappers>
        <mapper class="com.wanjl.dao.BookMapper"/>
    </mappers>
</configuration>

8.编写service层的接口和实现类

service接口

package com.wanjl.service;

import com.wanjl.pojo.Books;

import java.util.List;

public interface BookService {
    //添加图书
    int addBook(Books books);
    //修改图书
    int updateBook(Books books);
    //删除图书
    int deleteBookById(int id);
    //查询一本图书
    Books queryBookById(int id);
    //查询所有图书
    List<Books> queryAllBook();

}

service实现类

package com.wanjl.service;

import com.wanjl.dao.BookMapper;
import com.wanjl.pojo.Books;

import java.util.List;

public class BookServiceImpl implements BookService {
    //调用dao层的操作，设置一个set接口，方便Spring管理
    private BookMapper bookMapper;

    public void setBookMapper(BookMapper bookMapper) {
        this.bookMapper = bookMapper;
    }

    @Override
    public int addBook(Books books) {
        return bookMapper.addBook(books);
    }

    @Override
    public int updateBook(Books books) {
        return bookMapper.updateBook(books);
    }

    @Override
    public int deleteBookById(int id) {
        return bookMapper.deleteBookById(id);
    }

    @Override
    public Books queryBookById(int id) {
        return bookMapper.queryBookById(id);
    }

    @Override
    public List<Books> queryAllBook() {
        return bookMapper.queryAllBook();
    }
}