play.exceptions.JavaExecutionException:加载时需要加载id

Question

我不经常在"User.findById(user_id)"收到错误,但有时候,我不知道为什么.是什么导致这个错误？

注意:我正在使用Play版本1.2.3

谢谢.

抛出异常的函数;

public static void getMemberProfile(Long user _id){
       User sessionUser = getUser();
        User user = User.findById(user_id);

错误信息 ;

2012-02-12T13:06:42+00:00 app[web.1]: 
2012-02-12T13:06:42+00:00 app[web.1]: Execution exception (In /app/controllers/UserApi.java around line 470)
2012-02-12T13:06:42+00:00 app[web.1]: IllegalArgumentException occured : id to load is required for loading
2012-02-12T13:06:42+00:00 app[web.1]: 
2012-02-12T13:06:42+00:00 app[web.1]: play.exceptions.JavaExecutionException: id to load is required for loading
2012-02-12T13:06:42+00:00 app[web.1]:   at play.mvc.ActionInvoker.invoke(ActionInvoker.java:229)
2012-02-12T13:06:42+00:00 app[web.1]:   at Invocation.HTTP Request(Play!)
2012-02-12T13:06:42+00:00 app[web.1]: Caused by: java.lang.IllegalArgumentException: id to load is required for loading
2012-02-12T13:06:42+00:00 app[web.1]:   at org.hibernate.event.LoadEvent.<init>(LoadEvent.java:89)
2012-02-12T13:06:42+00:00 app[web.1]:   at org.hibernate.event.LoadEvent.<init>(LoadEvent.java:61)
2012-02-12T13:06:42+00:00 app[web.1]:   at org.hibernate.impl.SessionImpl.get(SessionImpl.java:1002)
2012-02-12T13:06:42+00:00 app[web.1]:   at org.hibernate.impl.SessionImpl.get(SessionImpl.java:998)
2012-02-12T13:06:42+00:00 app[web.1]:   at org.hibernate.ejb.AbstractEntityManagerImpl.find(AbstractEntityManagerImpl.java:614)
2012-02-12T13:06:42+00:00 app[web.1]:   at org.hibernate.ejb.AbstractEntityManagerImpl.find(AbstractEntityManagerImpl.java:589)
2012-02-12T13:06:42+00:00 app[web.1]:   at play.db.jpa.JPQL.findById(JPQL.java:34)
2012-02-12T13:06:42+00:00 app[web.1]:   at models.User.findById(User.java)
2012-02-12T13:06:42+00:00 app[web.1]:   at controllers.UserApi.getMemberProfile(UserApi.java:470)
2012-02-12T13:06:42+00:00 app[web.1]:   at play.mvc.ActionInvoker.invokeWithContinuation(ActionInvoker.java:546)
2012-02-12T13:06:42+00:00 app[web.1]:   at play.mvc.ActionInvoker.invoke(ActionInvoker.java:500)
2012-02-12T13:06:42+00:00 app[web.1]:   at play.mvc.ActionInvoker.invokeControllerMethod(ActionInvoker.java:476)
2012-02-12T13:06:42+00:00 app[web.1]:   at play.mvc.ActionInvoker.invokeControllerMethod(ActionInvoker.java:471)
2012-02-12T13:06:42+00:00 app[web.1]:   at play.mvc.ActionInvoker.invoke(ActionInvoker.java:159)

Answer 1

您得到此异常是因为您将null传递user_id给方法.

它很容易找到

• 阅读错误消息
• 阅读的源代码 org.hibernate.event.LoadEvent