Hibernate 级联添加删除

问题描述：实体类答案从属于实体类问题。（一对多）
 
    /**
     * 添加 问题 和 选项
     * @throws Exception
     */@Test
    public void testQu() throws Exception {
        Session session = HibernateUtil.currentSession();
        Transaction tr = session.beginTransaction();
        
        //级联添加
        Set options = new HashSet();
        Options op1 = new Options();
        op1.setName("op1");
        options.add(op1);
        
        
        Options op2 = new Options();
        op2.setName("op2");
        options.add(op2);
        
        
        Options op3 = new Options();
        op3.setName("op3");
        options.add(op3);
        Problems problems = new Problems();
        
        problems.setName("problem_1");
        problems.setOptions(options);
        problems.setTdesc("tdesc");
        problems.setType(1);
        
        Long ll = (Long)session.save(problems);
        
        
        System.out.println(ll);
        tr.commit();
        
mysql> select * from options ;
+----+------------+--------+------+---------+
| id | problemsid | answer | name | visible |
+----+------------+--------+------+---------+
|  1 |          1 |   NULL | op2  |       0 |
|  2 |          1 |   NULL | op3  |       0 |
|  3 |          1 |   NULL | op1  |       0 |
+----+------------+--------+------+---------+
3 rows in set (0.00 sec)

mysql> select * from problems ;
+----+-----------+------+-------+------------+---------+
| id | name      | type | tdesc | questionid | visible |
+----+-----------+------+-------+------------+---------+
|  1 | problem_1 |    1 | tdesc |       NULL |       0 |
+----+-----------+------+-------+------------+---------+
1 row in set (0.00 sec)

        
        //级联删除
        tr.begin();
            session.delete( session.get(Problems.class,ll) );
        tr.commit();

mysql> select * from problems ;
Empty set (0.00 sec)

mysql> select * from options ;
Empty set (0.00 sec) 

        HibernateUtil.closeSession();
    }
Options类
.......
    /**
     * @hibernate.many-to-one 
     *         cascade = "save-update"
     *         column = "Problemsid"
     *         class = "com.zhongqi.domain.Problems"
     * @return
     */
    public Problems getProblems() {
        return problems;
    }
............

Problems 类
    /**
     * @hibernate.set
     *         cascade="all-delete-orphan"
     *         inverse = "false"
     *         lazy = "true"
     *         @hibernate.collection-key  column = "problemsid"
     *         @hibernate.collection-one-to-many class = "com.zhongqi.domain.Options"
     * @return
     */
    public Set getOptions() {
        return options;
    }