问题
I just "discovered" that we have two Meta-Inf folders ... In eclipse and also in the War file.
The First one is (in the war):
/META-INF/
The Second, and weird one ist:
/WEB-INF/classes/META-INF/
In the second folder is a persistance.xml and a something.taglib.xml...
If i move the files into the first meta-inf folder i get exceptions from hibernate..
What is the purpose of this second and oddly placed meta-inf folder ?
Is this a normal folder structure ?
回答1:
The "weird one" location is correct; JSR-220/JSR-317 (Java Persistence API 1.0/2.0) in section 6.2/8.2 say:
The jar file or directory whose META-INF directory contains the persistence.xml file is termed the root of the persistence unit. In Java EE, the root of a persistence unit may be one of the following:
- an EJB-JAR file
- the WEB-INF/classes directory of a WAR file
- a jar file in the WEB-INF/lib directory of a WAR file
- a jar file in the root of the EAR*
- a jar file in the EAR library directory
- an application client jar file.
*) Only valid for JPA 1.0
So, directly in a WAR file, the only correct location is WEB-INF/classes/META-INF/.
来源：https://stackoverflow.com/questions/13238615/two-meta-inf-folders-normal-structure