Step-by-Step Guide to Configuring MyBatis Generator and Generating Code in a Spring Boot Project

1. Copy the MyBatis Generator configuration file (GeneratorMapper.xml) to the root directory of your project.

2. Modify

<generatorConfiguration>...</generatorConfiguration>

according to your project and database tables, updating the driver class to com.mysql.cj.jdbc.Driver for newer MySQL versions and adding nullCatalogMeansCurrent=true to the JDBC URL to avoid generation issues.

Note: The current MySQL version in the example is 5.7; adjust settings based on your environment.

3. Add the MySQL reverse‑engineering dependency to pom.xml:

<build>
  <plugins>
    <plugin>
      <groupId>org.mybatis.generator</groupId>
      <artifactId>mybatis-generator-maven-plugin</artifactId>
      <version>1.3.6</version>
      <configuration>
        <configurationFile>GeneratorMapper.xml</configurationFile>
        <verbose>true</verbose>
        <overwrite>true</overwrite>
      </configuration>
    </plugin>
  </plugins>
</build>

4. Run the Maven goal to generate the files (e.g., mvn mybatis-generator:generate), then double‑click the generated files to view them.

5. The generation creates the following artifacts: Student.java – the model class with fields id, name, and age. StudentMapper.java – the mapper interface with CRUD methods. StudentMapper.xml – the MyBatis XML mapping file defining result maps and SQL statements.

Example of the generated model class:

package com.md.springboot.model;

public class Student {
    private Integer id;
    private String name;
    private Integer age;
    public Integer getId() { return id; }
    public void setId(Integer id) { this.id = id; }
    public String getName() { return name; }
    public void setName(String name) { this.name = name; }
    public Integer getAge() { return age; }
    public void setAge(Integer age) { this.age = age; }
}

Example of the generated mapper interface:

package com.md.springboot.mapper;

import com.md.springboot.model.Student;

public interface StudentMapper {
    int deleteByPrimaryKey(Integer id);
    int insert(Student record);
    int insertSelective(Student record);
    Student selectByPrimaryKey(Integer id);
    int updateByPrimaryKeySelective(Student record);
    int updateByPrimaryKey(Student record);
}

Example of the generated StudentMapper.xml mapping file (truncated for brevity):

<?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.md.springboot.mapper.StudentMapper">
  <resultMap id="BaseResultMap" type="com.md.springboot.model.Student">
    <id column="id" jdbcType="INTEGER" property="id"/>
    <result column="name" jdbcType="VARCHAR" property="name"/>
    <result column="age" jdbcType="INTEGER" property="age"/>
  </resultMap>
  ...
</mapper>

These generated files simplify database operations in the Spring Boot project, allowing you to focus on business logic.