Insert CLOB into oracle under weblogic

Question

Situation: running my servlet under weblogic, want to insert more than 4000 characters into CLOB of oracle 8.1.7
Problem: cannot be done by using code which is able to do it under tomcat
i use this code in tomcat:
import java.sql.*;
import oracle.sql.CLOB;
import oracle.jdbc.driver.OracleResultSet;
con.setAutoCommit(false);
Statement stmt = con.createStatement();
rs = stmt.executeQuery("SELECT clob_field FROM table where rid=id FOR UPDATE");
rs.next();
CLOB clob = ((OracleResultSet)rs).getCLOB(1);
Writer writer = clob.getCharacterOutputStream();
writer.write(dataString);
writer.close()l
con.commit();
con.setAutoCommit(true);
stmt.close();
after that i know that i can't use API of oracle when i'm using weblogic (e.g. oracle.sql.CLOB)
and i find this code from other user:
import weblogic.jdbc.vendor.oracle.OracleThinClob;
import java.io.*;
import java.sql.*;
PreparedStatement stmt = con.prepareStatement ( "INSERT INTO database VALUES ( ?, EMPTY_CLOB() )" );
stmt.setInt ( 1, 1 );
// inserts a new entry with an empty clob object
stmt.executeUpdate ();
if ( stmt != null )
stmt.close();
// retrieves CLOB-Object
stmt = con.prepareStatement ( "SELECT clob_field FROM database WHERE id=?" );
stmt.setInt ( 1, 1 );
ResultSet rs = stmt.executeQuery ( );
if ( rs.next() )
Clob cl = rs.getClob(1);
Writer clobWriter = ((OracleThinClob)cl).getCharacterOutputStream();
// Open the sample file as a stream for insertion into the Clob column
File testFile = new File ( "file.txt" );
FileReader testReader = new FileReader ( testFile );
// buffer to hold data to being written to the clob.
char[] cBuffer = new char[((OracleThinClob)cl).getBufferSize()];
// Read data from file, write it to clob
int iRead = 0;
while( (iRead= testReader.read(cBuffer)) != -1 )
clobWriter.write( cBuffer, 0, iRead);
testReader.close();
clobWriter.close();
if ( rs != null )
rs.close();
if ( stmt != null )
stmt.close();
// update clob-data in database
stmt = con.prepareStatement ( "UPDATE database SET clob_field = ? WHERE id = ?" );
stmt.setClob ( 1, cl );
stmt.setInt ( 2, 1 );
stmt.executeUpdate();
it throws java.lang.ClassCastException: oracle.sql.CLOB
but i haven't imported or used any API from oracle.........
please help
thanks

Answer 1

hi,
unfortunatly, you can't do this with welbogic6.1 because it 'manage' itself oracle librairies (weblogic.jar),
here is the way i solved the pb for BLOB :
i replaced :
BLOB blob = ((OracleResultSet)rs).getBLOB(1);
by
weblogic.jdbc.rmi.SerialOracleBlob cast1 =(weblogic.jdbc.rmi.SerialOracleBlob)rs.getBlob("myBlob");
weblogic.jdbc.rmi.internal.OracleTBlobImpl cast2 =(weblogic.jdbc.rmi.internal.OracleTBlobImpl)cast1.getTheRealBlob();
BLOB myBlob = (oracle.sql.BLOB)cast2.getTheRealBlob();
it is the same for clob (i suppose ^_^)
hope this helps !
Badr.