多对多单向，多对多双向

多对多单向

Teacher类中

@ManyToMany
@JoinTable(name="student_teacher",//中间表名
joinColumns=@JoinColumn(name="teacher_id"),//这个类在表中的id
inverseJoinColumns=@JoinColumn(name="student_id")//反转的类在联合表中的id

)
public Set<Student> getStudentSet() {
return studentSet;
}

生成的sql

Hibernate: 
    create table Student (
        id integer not null auto_increment,
        name varchar(255),
        score integer not null,
        primary key (id)
    ) ENGINE=InnoDB
Hibernate: 
    create table student_teacher (
        teacher_id integer not null,
        student_id integer not null,
        primary key (teacher_id, student_id)
    ) ENGINE=InnoDB
Hibernate: 
    create table Teacher (
        id integer not null auto_increment,
        name varchar(255),
        primary key (id)
    ) ENGINE=InnoDB
Hibernate: 
    alter table student_teacher 
        add constraint FK1iasve8qh9avntdgaxoiguu0u 
        foreign key (student_id) 
        references Student (id)
Hibernate: 
    alter table student_teacher 
        add constraint FKarpd7go6oi75bga0d1soi9rsq 
        foreign key (teacher_id) 
        references Teacher (id)

多对多双向

Teacher类

@ManyToMany
@JoinTable(name="student_teacher",
joinColumns=@JoinColumn(name="teacher_id"),//这个类在表中的id
inverseJoinColumns=@JoinColumn(name="student_id")//反转的类在联合表中的id

)
public Set<Student> getStudentSet() {
return studentSet;
}

Student类

@ManyToMany(mappedBy="studentSet")
public Set<Teacher> getSet() {
return set;
}