[英]Why there is an Exception in thread “Tomcat JDBC Pool Cleaner”?
[英]Why is there “pool pool-1-thread-1” exception in Thread
如下代碼:
ExecutorService executor = newSingleThreadExecutor();
executor.execute(new Runnable()
{
@Override
public void run()
{
Session session = (Session) entityManager.getDelegate();
SQLQuery query = session.createSQLQuery("SELECT * FROM function()");
boolean result= (boolean) query.uniqueResult();
}
}
我有一個例外:
Exception in thread "pool-1-thread-1" java.lang.NullPointerException
at personDao$1.run(PersonDao.java:1080)
因此它說的是boolean result= (boolean) query.getUniqueResult();
,有一個池1線程1,為什么會發生這種情況?
名稱"pool-1-thread-1"
來自ExecutorService
。
如果您的信息表明該行發生了NPE
boolean resul t = (boolean) query.getUniqueResult();
是的,這可能是以下兩個原因之一:
query
為null
。 query.getUniqueResult()
返回null
,而(boolean) (Boolean) null throws NullPointerException
。
聲明:本站的技術帖子網頁,遵循CC BY-SA 4.0協議,如果您需要轉載,請注明本站網址或者原文地址。任何問題請咨詢:yoyou2525@163.com.