如何在grails ORM中对学生-班级关系进行建模？多对多关系

class Student {
    String name
    static hasMany = [classes: Class]
    static constraints = {
        name blank: false
    }
}

class Class {
    String name
    static hasMany = [students: Student]
    static constraints = {
        name blank: false
    }
}

grails dbm-create-changelog changelog.groovy

databaseChangeLog = {
    changeSet(author: "your_name", id: "create_student_class_tables") {
        createTable(tableName: "student") {
            column(name: "id", type: "bigint", autoIncrement: true, primaryKey: true)
            column(name: "name", type: "varchar(255)")
        }
        createTable(tableName: "class") {
            column(name: "id", type: "bigint", autoIncrement: true, primaryKey: true)
            column(name: "name", type: "varchar(255)")
        }
        createTable(tableName: "student_class") {
            column(name: "student_id", type: "bigint")
            column(name: "class_id", type: "bigint")
        }
        addPrimaryKey(tableName: "student_class", columnNames: "student_id, class_id")
        addForeignKeyConstraint(baseTableName: "student_class", baseColumnNames: "student_id", referencedTableName: "student", referencedColumnNames: "id")
        addForeignKeyConstraint(baseTableName: "student_class", baseColumnNames: "class_id", referencedTableName: "class", referencedColumnNames: "id")
    }
}

grails dbm-update

// 创建学生和班级
def student1 = new Student(name: "Alice")
def student2 = new Student(name: "Bob")
def class1 = new Class(name: "Math")
def class2 = new Class(name: "English")

// 添加学生到班级
class1.addToStudents(student1)
class1.addToStudents(student2)
class2.addToStudents(student1)

// 保存学生和班级
student1.save()
student2.save()
class1.save()
class2.save()

// 获取学生所属的班级
def student = Student.get(1)
def classes = student.classes

// 获取班级中的学生
def clazz = Class.get(1)
def students = clazz.students