hibernate中多对多的映射文件配置

student.hbm.xml

<?xml version="1.0" encoding="UTF-8"?>
<!DOCTYPE hibernate-mapping PUBLIC 
    "-//Hibernate/Hibernate Mapping DTD 3.0//EN"
    "http://www.hibernate.org/dtd/hibernate-mapping-3.0.dtd">
    
    <hibernate-mapping package="com.kaishengit.pojo">
			<class name="Student" table="t_student">
				<id name="id" column="id">
					<generator class="native"></generator>
				</id>
				<property name="name" column="name"></property>
				<set name="teacherSet" table="t_student_teacher">
					<key column="student_id"></key>
					<many-to-many class="Teacher" column="teacher_id"></many-to-many>
				</set>
			</class>
		
    </hibernate-mapping>

teacher.hbm.xml

<?xml version="1.0" encoding="UTF-8"?>
<!DOCTYPE hibernate-mapping PUBLIC 
    "-//Hibernate/Hibernate Mapping DTD 3.0//EN"
    "http://www.hibernate.org/dtd/hibernate-mapping-3.0.dtd">
    
    <hibernate-mapping package="com.kaishengit.pojo">
			<class name="Teacher" table="t_teacher">
				<id name="id" column="id">
					<generator class="native"></generator>
				</id>
				<property name="name" column="name"></property	>
				<set name="studentSet" table="t_student_teacher">
					<key column="teacher_id"></key>
					<many-to-many class="Student" column="student_id"></many-to-many>
				</set>
			</class>
		
    </hibernate-mapping>