By W.ZH Sept 1 2011
When I use the Clob and Blob in the DB, such as try to use ADF-BC to retrieve them out , it can not be converted to string from the blob domain object. System log shows that read out blob data is a weblogic.jdbc.wrapper.Clob_weblogic_jdbc_base_Base Object. So it gets conversion error.
Another problem you may facing is that, when you try to write a clob data into the DB by commit, you get an error like this:
“java.lang.NullPointException at oracle.domain.ClobDomain.writerCharsToClob (……)”
This issue also is caused by same reason.
In the Data Soruce configuration In Weblogic, there is a flag can control this:
Admin Console –> DataSource–> your DS–> Connection pool –>Advanced–>
There is check box for “Wrap Data Types”, uncheck this , restart your WLS to test again. you will see the db data readout will be sql blob….