CLOB.createTemporary gives Nullpointer Exception

Question

Hello,
I'm trying to create a temporary clob in my java code, but when I run the program I get the following exception.
java.lang.NullPointerException
     at oracle.sql.LobPlsqlUtil.plsql_createTemporaryLob(LobPlsqlUtil.java:1354)
     at oracle.jdbc.dbaccess.DBAccess.createTemporaryLob(DBAccess.java:997)
     at oracle.sql.LobDBAccessImpl.createTemporaryClob(LobDBAccessImpl.java:240)
     at oracle.sql.CLOB.createTemporary(CLOB.java:527)
     at org.tennet.utils.bc4j.ApplicationModuleImpl.createClob(ApplicationModuleImpl.java:278)
     at org.tennet.utils.bc4j.ApplicationModuleImpl.createClobDomain(ApplicationModuleImpl.java:299)
     at org.tennet.nevada.loader.ResultLoader.executeProcedure(ResultLoader.java:243)
     at org.tennet.nevada.loader.ResultLoader.process(ResultLoader.java:77)
     at org.tennet.nevada.broker.processor.RequestProcessor.processResult(RequestProcessor.java:374)
     at org.tennet.nevada.broker.processor.LoadFlowVAProcessor.process(LoadFlowVAProcessor.java:132)
     at org.tennet.nevada.broker.RequestHandler.processRequest(RequestHandler.java:289)
     at org.tennet.nevada.broker.RequestHandler.run(RequestHandler.java:137)
This error started when I began using Data Sources instate of direct JDBC Connections.
The problem is there is no source available for this class so I can’t look what is causing the Nullpointer Exception.
Can someone tell me what is causing this problem?
Regards,
Dennis Labordus

Answer 1

Hi Dennis,
I have had the same problem as this. I am going to get onto Oracle via Metalink about it.
However - there is a work around.
We are using OC4J with its data sources.
There is a method on the OC4J Connection called getCoreConnection(Connection). This returns the underlying Oracle connection.
If you then pass this underlying oracle connection to CLOB.createTemporary() it works.
We had to use reflection to call the method as I couldn't seem to cast it statically.
Paul McHugh
* getOracleConnection
* Derive oracle connection from DataSource connection
private static OracleConnection getOracleConnection (Connection connection) throws SQLException
System.err.println ("UserTypeImpl.getOracleConnection: " + connection);
* Check for an existing oracle connection
* This should be the case in a database deployment
if (connection instanceof oracle.jdbc.driver.OracleConnection)
System.err.println (" Connection is already the base Oracle Connection" + connection);
return (OracleConnection) connection;
* Check for an OC4J deployment
else
System.err.println (" Searching for core connection ...");
Object conObj = (Object) connection;
Class conclass = conObj.getClass();
OracleConnection coreCon = null;
Method meth = null;
// Locate method getCoreConnection on Orion data source
try {
Class[] parameterTypes = new Class[] {java.sql.Connection.class};
meth = conclass.getMethod("getCoreConnection", parameterTypes);
} catch (NoSuchMethodException e)
e.printStackTrace();
throw new SQLException ("UserTypeImpl.getOracleConnection: No such method: getCoreConnection: " + e);
// Invoke method getCoreConnection on orion data source
try {
Object[] args = new Object[] {connection};
coreCon = (OracleConnection) meth.invoke(conObj, args);
catch (InvocationTargetException e)
e.printStackTrace();
throw new SQLException ("UserTypeImpl.getOracleConnection: Invoke: getCoreConnection: " + e);
catch (IllegalAccessException e)
e.printStackTrace();
throw new SQLException ("UserTypeImpl.getOracleConnection: Invoke: getCoreConnection: " + e);
if (coreCon != null)
System.err.println (" Core connection found: " + coreCon);
return coreCon;
} else
System.err.println (" Unable to locate core connection.");
throw new SQLException ("UserTypeImpl.getOracleConnection: Unable to locate core oracle connection.");