我正在使用jpa创建Java EE应用程序.
当代码在服务器上运行时,我收到以下错误
[2/25/12 22:56:31:371 IST] 00000047 SystemOut O hello
[2/25/12 22:56:31:375 IST] 00000047 SystemOut O Error...:(
[2/25/12 22:56:31:371 IST] 00000047 SystemErr R java.lang.NullPointerException
[2/25/12 22:56:31:371 IST] 00000047 SystemErr R at plh.service.ejb.UserBean.getUserDetails(UserBean.java:41)
[2/25/12 22:56:31:372 IST] 00000047 SystemErr R at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
[2/25/12 22:56:31:372 IST] 00000047 SystemErr R at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:45)
[2/25/12 22:56:31:372 IST] 00000047 SystemErr R at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:37)
[2/25/12 22:56:31:372 IST] 00000047 SystemErr R at java.lang.reflect.Method.invoke(Method.java:599)
[2/25/12 22:56:31:372 IST] 00000047 SystemErr R at com.ibm.etools.utc.model.ReflectionMethodModel.invoke(ReflectionMethodModel.java:65)
[2/25/12 22:56:31:372 IST] 00000047 SystemErr R at …我正在创建一个拥有40多个数据库表的Java EE项目.哪个持久性API更适合用于这样的项目:hibernate/jpa等.
即使在谷歌上,我找不到与此场景相对应的任何帖子.