Question

hibernate query java.lang.NullPointerException问题

public List findOpenByUploader(String uploader){
try {
Query query = getSession().createQuery("from ProblemStatus s where s.defunct =:defunct and s.uploader =:uploader order by s.id");
query.setString("uploader", uploader);
query.setParameter("defunct", "N");
return query.list();

} catch (RuntimeException re) {
log.error("find by property name failed", re);
throw re;
}
}
抛出错误的语句是return query.list();，抛出java.lang.NullPointerException
问题在query.setString("uploader", uploader);中，
当uploader为字母开头的字符串时，不会抛出错误信息，如uploader为“root”
但当uploader为数字开头的字符串时，死活都抛出如上错误信息，如uploader为“012345”

query.setString("uploader", uploader);改为下面的任意一种都一样抛出错误信息
query.setString("uploader", ""+uploader);
query.setParameter("uploader", ""+uploader);
query.setParameter("uploader", uploader);
query.setParameter("uploader", uploader,Hibernate.STRING);

请高手指点
非常skshinji感谢！
按照您的方法修改，或抛出无改参数的错误
java.lang.IllegalArgumentException: Parameter uploader does not exist as a named parameter in [from ProblemStatus s where s.defunct =:defunct and s.uploader =':uploader' order by s.id]

Answer 1

from ProblemStatus s where s.defunct =:defunct and s.uploader =:uploader order by s.id

ProblemStatus s 自动生成的中间有个as

如 from ProblemStatus as s where s.defunct =:defunct and s.uploader =:uploader order by s.id

至于Query 的setString 方法对于数字应该没什么问题除了你的Hibernate包有问题，或者配置地方弄错了

Answer 2

Query query = getSession().createQuery("from ProblemStatus s where s.defunct =:defunct and s.uploader =':uploader' order by s.id");

把sql改成这样试试是不是可以。看你的样子是把字符串型的误认为是数字了

Answer 3

代码太少，异常太少。估计是(List)all这里为空，很有可能是super.getSession()并未拿到Session,可以分两步把这里的代码改写一下。