mybatis-plus使用注解方式实现递归

service层

/**
     * 获取所有部门
     * @return
     */
    @Override
    public List<Department> getAllDepartments() {
        return departmentMapper.getAllDepartments();
    }

mapper层

/**
     * 查询所有部门
     * @return
     */
    @Select("select * from t_department where parent_id = 0")
    @Results(id = "departmentMap",value = {
            @Result(property = "id",column = "id"),
            @Result(property = "name",column = "name"),
            @Result(property = "parentId",column = "parent_id"),
            @Result(property = "depPath",column = "dep_path"),
            @Result(property = "enabled",column = "enabled"),
            @Result(property = "isParent",column = "is_parent"),
            @Result(property = "children",column = "id",many = @Many(select = "getAllDepartmentsId")),//这里表示一对多 一里面包含多
    })
    List<Department> getAllDepartments();

    @Select("select * from t_department where parent_id = #{parent_id}")
    @ResultMap("departmentMap")
    List<Department> getAllDepartmentsId();

children: 它是在实体类定义的字段 private List children;
id = "departmentMap": 通过注解@Results来指定对应关系 指定@ResultMap("departmentMap")
column指定数据库字段的名称，property指定实体类属性的名称，jdbcType数据库字段类型，@Result里的id值为true表明主键，默认false