此文章需根据上一节Mybatis-Plus入门知识

需求准备：两张数据表，两个实体类，两个Mapper，两个Service，如图：

 第一种方法：

List<Student> studentList = iStudentMapper.list();
        System.out.println("学生表数据:"+studentList);

        List<Teacher> teacherList=new ArrayList<>();
        for (Student student:studentList) {
            Teacher teacher=new Teacher();
            teacher.setId(student.getId());
            teacher.setName(student.getName());
            teacher.setAge(student.getAge());
            teacher.setSex(student.getSex());
            teacher.setAddress(student.getAddress());
            teacherList.add(teacher);
        }
        iTeacherMapper.saveBatch(teacherList);

第二种方法（BeanUtils.copyProperties）：

 List<Student> studentList = iStudentMapper.list();
        List<Teacher> teacherList=new ArrayList<>();

        for (Student student:studentList) {
            Teacher teacher=new Teacher();
            BeanUtils.copyProperties(student,teacher);
            teacherList.add(teacher);
        }
        iTeacherMapper.saveBatch(teacherList);

第三种方法（Hutool工具）（推荐）

需导入依赖项：

        <dependency>
            <groupId>cn.hutool</groupId>
            <artifactId>hutool-all</artifactId>
            <version>5.8.16</version>
        </dependency>
        <dependency>
            <groupId>cglib</groupId>
            <artifactId>cglib</artifactId>
            <version>3.1</version>
            <scope>compile</scope>
        </dependency>