常见Hibernate报错处理：出现“org.hibernate.QueryException: could not resolve property”和 is not mapped和could no...

　　正确写法：

　　@Override
    @SuppressWarnings("unchecked")
    public List<Device> queryOSDevice(String cpu){
        String sql = null;
        if(cpu.equals("os_xp")){
            sql = "from "+this.clazz.getName()+" this WHERE this.os.id = (select id from Os o where o.name = 'com.vrv.common.system.os.WindowsXP') ";
        }else if(cpu.equals("os_7")){
            sql = "from "+this.clazz.getName()+" this WHERE this.os.id = (select id from Os o where o.name = 'com.vrv.common.system.os.Windows7') ";
        }else if(cpu.equals("Os_Win8")){
            sql = "from "+this.clazz.getName()+" this WHERE this.os.id = (select id from Os o where o.name = 'com.vrv.common.system.os.Windows81') ";
        }else if(cpu.equals("Os_Win10")){
            sql = "from "+this.clazz.getName()+" this WHERE this.os.id = (select id from Os o where o.name = 'com.vrv.common.system.os.Windows10InsiderPreview') ";
        }else if(cpu.equals("os_vista")){
            sql = "from "+this.clazz.getName()+" this WHERE this.os.id = (select id from Os o where o.name = 'com.vrv.common.system.os.WindowsVista') ";
        }else if(cpu.equals("os_2003")){
            sql = "from "+this.clazz.getName()+" this WHERE this.os.id = (select id from Os o where o.name = 'com.vrv.common.system.os.WindowsServer2003') ";
        }else if(cpu.equals("os_98")){
            sql = "from "+this.clazz.getName()+" this WHERE this.os.id = (select id from Os o where o.name = 'com.vrv.common.system.os.Windows98') ";
        }else if(cpu.equals("os_95")){
            sql = "from "+this.clazz.getName()+" this WHERE this.os.id = (select id from Os o where o.name = 'com.vrv.common.system.os.Windows95') ";
        }else if(cpu.equals("os_me")){
            sql = "from "+this.clazz.getName()+" this WHERE this.os.id = (select id from Os o where o.name = 'com.vrv.common.system.os.WindowsMe') ";
        }else if(cpu.equals("os_nt")){
            sql = "from "+this.clazz.getName()+" this WHERE this.os.id = (select id from Os o where o.name = 'com.vrv.common.system.os.WindowsNt') ";
        }else if(cpu.equals("os_2000")){
            sql = "from "+this.clazz.getName()+" this WHERE this.os.id = (select id from Os o where o.name = 'com.vrv.common.system.os.Windows2000') ";
        }
        return getSession().createQuery(sql).list();
    }

1、出现“org.hibernate.QueryException: could not resolve property”错误的解决：

　　起初，hql语句是这样写的，报错：could not resolve property：osId

 sql = "from "+this.clazz.getName()+" this WHERE this.osId = (select id from cems_dict_os o where o.name = 'com.vrv.common.system.os.WindowsXP') ";

　　考虑需要改为  this.os.id ，但是又出现cems_dict_os is not mapped的错误

sql = "from "+this.clazz.getName()+" this WHERE this.os.id = (select id from cems_dict_os o where o.name = 'com.vrv.common.system.os.WindowsXP') ";

2、出现“cems_dict_os is not mapped”错误的解决：

　　hql语句都需要从对象里面获取，所以需要将  cems_dict_os  改成它的实体对象  Os

sql = "from "+this.clazz.getName()+" this WHERE this.os.id = (select id from Os o where o.name = 'com.vrv.common.system.os.WindowsXP') ";

3、org.hibernate.QueryParameterException: could not locate named parameter [ip]

　　其实自己去检查一下SQL语句就可以了

　　①：参数不正确，基本上是" 实体属性=:参数属性 "（尤其是冒号：这个大家会经常丢掉）

　　②：画蛇添足，没有这个参数，自己认为新增的参数，导致找不到

　　我导致这个问题的原因是：and this.ip = :ip 写成了 this.ip = ? ；此外注意：  =:参数属性  ；冒号和参数属性之间不能有空格

4、SSH框架问题——node to traverse cannot be null!报错问题：java.lang.IllegalArgumentException: node to traverse cannot be null!

　　这个错误一般是sql、hql语句有问题，比如关键字书写问题，语法问题等，本人犯了一个低级错误，使用update的时候，给多个属性赋值需要使用“，”（逗号）隔开。

5、org.hibernate.QueryException: Not all named parameters have been set: [name]：

if(!"".equals(name)){
    sql += "and this.name = :name ";
}
osDevice = getSession().createQuery(sql).setParameter("name",name).list();

　　这样写就会报这个错误，原因是：hibernate 执行sql时没有找到相应的参数名，改为下面这样既可：

if(!"".equals(name)){
    sql += "and this.name = '" + name + "'";
}
osDevice = getSession().createQuery(sql).list();