JAVA测试类调用DAO层查询数据库空指针异常

此为DAOImpl类 public TbAssignment loadByLoginName(String loginName) { System.out.println(loginName); String hqlString = " from TbAssignment u where u.tbUser.userLoginname='"+loginName+"' "; List list = th... 此为DAOImpl类 public TbAssignment loadByLoginName(String loginName) { System.out.println(loginName); String hqlString = " from TbAssignment u where u.tbUser.userLoginname='"+loginName+"' "; List list = this.getHibernateTemplate().find(hqlString); if (list != null && list.size() > 0) { return (TbAssignment) list.get(0); } else { return null; } } 测试类 @Test public void t_pwd (){ TbAssignmentDaoImpl tbd = new TbAssignmentDaoImpl(); TbAssignment tb =tbd.loadByLoginName("XXXX"); System.out.println(tb.getTbUser().getUserLoginpwd()); }