CastCastException with OracleCallableStatement

Question

I'm trying to use Oracle JDBC extensions with the Oracle thin Driver (to
read a cursor returned by a PL/SQL function). When I attempt to cast a
CallableStatement to an weblogic.jdbc.vendor.oracle.OracleCallableStatement,
the weblogic wrapper class, I still get the same ClassCastException as if I
try to cast to a vanilla OracleCallableStatement. I thought the weblogic
class was the fix to this problem.
Code is:
ResultSet rs =
((weblogic.jdbc.vendor.oracle.OracleCallableStatement)cs).getCursor(1);
Exception is:
java.sql.SQLException: java.lang.ClassCastException:
oracle.jdbc.driver.OracleCallableStatement
It's interesting that the exception is for
oracle.jdbc.driver.CallableStatement, even though I'm casting to the
Weblogic wrapper class.
Weblogic version is 6.1 sp2
Oracle is 8.1.6
Does anyone know what's happeneng here, and how to fix it.
Any help much appreciated
John

Answer 1

Unfortunatly, this doesn't work either - it doesn't understand the new type:
java.sql.SQLException: Invalid column type
at oracle.jdbc.dbaccess.DBError.throwSqlException(DBError.java:180)
at oracle.jdbc.dbaccess.DBError.throwSqlException(DBError.java:222)
at oracle.jdbc.dbaccess.DBError.throwSqlException(DBError.java:285)
at
oracle.jdbc.driver.OracleStatement.get_internal_type(OracleStatement.java:53
40)
at
oracle.jdbc.driver.OracleCallableStatement.registerOutParameter(OracleCallab
leStatement.java:245)
at
oracle.jdbc.driver.OracleCallableStatement.registerOutParameter(OracleCallab
leStatement.java:370)
at
weblogic.jdbc.jts.Statement.registerOutParameter(Statement.java:973)
at
weblogic.jdbc.rmi.internal.CallableStatementImpl.registerOutParameter(Callab
leStatementImpl.java:53)
at
weblogic.jdbc.rmi.SerialCallableStatement.registerOutParameter(SerialCallabl
eStatement.java:48)
at com.bluedot.beans.support.ProcedureBuffer.executeFunction(Unknown
Source)
at
com.bluedot.beans.support.ProcedureBuffer.executeTagSetFunction(Unknown
Source)
at
com.bluedot.beans.entityManagement.EntityManagementServerBean.getExhibitorSt
ats(Unknown Source)
at
com.bluedot.beans.entityManagement.EntityManagementServerBean_7yjcm7_EOImpl.
getExhibitorStats(EntityManagemen
tServerBean_7yjcm7_EOImpl.java:37)
etc
"Slava Imeshev" <[email protected]> wrote in message
news:[email protected]...
OK. Now it's clear. You can not use OracleTypes.CURSOR.
In order to get a result set from cursor, the right sequence
should be following:
cs.registerOutParameter(1, java.sql.Types.OTHER);
cs.execute();
ResultSet rs = cstmt.getResultSet(1);
Regards,
Slava Imeshev
"John Prout" <[email protected]> wrote in message
news:[email protected]...
Slava
Here's part of the stack trace - the whole thing is probably 100 lines:
java.sql.SQLException: java.lang.ClassCastException:
oracle.jdbc.driver.OracleCallableStatement
at
weblogic.jdbc.jts.CallableStatement.getCursor(CallableStatement.java:277)
at
weblogic.jdbc.rmi.internal.CallableStatementImpl.getCursor(CallableStatement
Impl.java:420)
at
weblogic.jdbc.rmi.SerialCallableStatement.getCursor(SerialCallableStatement.
java:496)
at
com.bluedot.beans.support.ProcedureBuffer.executeTagSetFunction(Unknown
Source)
at
com.bluedot.beans.entityManagement.EntityManagementServerBean.getExhibitorSt
ats(Unknown Source)
at
com.bluedot.beans.entityManagement.EntityManagementServerBean_7yjcm7_EOImpl.
getExhibitorStats(EntityManagemen
tServerBean_7yjcm7_EOImpl.java:421)
at
com.bluedot.beans.entityManagement.EntityManagementServerBean_7yjcm7_EOImpl_
WLSkel.invoke(Unknown Source)
at
weblogic.rmi.internal.BasicServerRef.invoke(BasicServerRef.java:296)
As you can see, the PL/SQL code is being called from an EJB.
The connection is obtained through JNDI:
java.sql.Connection conn = null;
Hashtable ht = new Hashtable() ;
ht.put( Context.INITIAL_CONTEXT_FACTORY ,
"weblogic.jndi.WLInitialContextFactory" );
InitialContext ctx = new InitialContext( ht ) ;
if ( ctx == null ) return null ;
String dataSource = getUserSession().getDatabase() ;
javax.sql.DataSource source = (javax.sql.DataSource) ctx.lookup(
dataSource ) ;
if ( source != null )
conn = source.getConnection() ;
Then the CallableStatement is obtained and used:
OracleConnection con = null ;
OracleCallableStatement cs = null ;
Object returnValue = null;
ResultSet rs = null ;
// String in the form: { ? = call <procedure-name>[<arg1>,<arg2>,...]}
StringBuffer buff = new StringBuffer();
buff.append("{ ? = call ").append(functionName).append("()") ;
// setup mStringBuffer and mStringLength so the rest of the class will
work right
buff.getChars(0, buff.length(),mStringBuffer,0);
mStringLength = buff.length();
con = (OracleConnection)psc.getDatabaseConnection() ;
cs = (OracleCallableStatement)con.prepareCall( buff.toString() ) ;
cs.registerOutParameter(1, OracleTypes.CURSOR);
// printQuery( psc ) ;
boolean result = cs.execute() ; // It's not in the API what "result"
is...
rs =
((weblogic.jdbc.vendor.oracle.OracleCallableStatement)cs).getCursor(1);
The exception happens when I call getCursor(1)
This code works outside weblogic, using a connection I obtain usingstandard
JDBC and the Oracle thin driver.
The sample is extracted from several pieces of the real code, so therecould
be compile errors, etc
John
"Slava Imeshev" <[email protected]> wrote in message
news:[email protected]...
Hi John,
Could you post the questionable code and the full exception?
From information provided it's not clear whether this exception
is thown from the server or from the app.
Regards,
Slava Imeshev
"John Prout" <[email protected]> wrote in message
news:[email protected]...
I am getting a connection from a standard weblogic connection pool,
using
a
JNDI lookup. I can see no way to directly obtain a
weblogic.jdbc.vendor.oracle.OracleConnection. If I cast everything to
the
weblogic OracleConnection and OracleCallableStatement, I still get thesame
ClassCastException
Can you post an example of how to get the
weblogic.jdbc.vendor.oracle.OracleConnection
Thanks
John
"Slava Imeshev" <[email protected]> wrote in message
news:[email protected]...
Hi John,
This exception is thrown because plain oracle connection was used.
To use weblogic oracle extensions, connection should be obtained
from the connection pool, either via DataSource or directly.
Regards,
Slava Imeshev
"John Prout" <[email protected]> wrote in message
news:[email protected]...
I'm trying to use Oracle JDBC extensions with the Oracle thin Driver
(to
read a cursor returned by a PL/SQL function). When I attempt to cast a
CallableStatement to anweblogic.jdbc.vendor.oracle.OracleCallableStatement,
the weblogic wrapper class, I still get the same ClassCastException as
if
I
try to cast to a vanilla OracleCallableStatement. I thought the
weblogic
class was the fix to this problem.
Code is:
ResultSet rs =
((weblogic.jdbc.vendor.oracle.OracleCallableStatement)cs).getCursor(1);
>>>
Exception is:
java.sql.SQLException: java.lang.ClassCastException:
oracle.jdbc.driver.OracleCallableStatement
It's interesting that the exception is for
oracle.jdbc.driver.CallableStatement, even though I'm casting to the
Weblogic wrapper class.
Weblogic version is 6.1 sp2
Oracle is 8.1.6
Does anyone know what's happeneng here, and how to fix it.
Any help much appreciated
John