Dealing with java.lang.ExceptionInInitializerError

I have seen so many articles on the web about java.lang.ExceptionInInitializerError, so many solutions and many ways to figure out any success support. Here I tell you the mine.

Problem:

BEGIN

*

ERROR at line 1:

ORA-29549: class UO_CODE.nz/xx/xxxx/db/file/Jfile has changed, Java session state cleared.

ORA-06512: at "UO_CODE.UO_XFILE", line 10

ORA-06512: at "UO_CODE.UO_XFILE", line 38

ORA-06512: at line 3

and then.....

Solution:

Check the permissions granted in:

select * from dba_java_policy;

Check carefully into your package if the code is intending to reach one database folder created if so, and the granted permissions have not been granted then...