Clob Handling In WebLogic 6.0 with SP1

Question

In Weblogic V5.10sp8
I have a block of code that looks up a very large clob and appends some
text to the end of it and
writes the new larger clob back to the same row same column.
part of the code looks like this.
char[] buffer = this.getBuffer():
java.sql.ResultSet rs = this.getResultSet();
oracle.sql.CLOB myClob =
(oracle.sql.CLOB)rs.getClob("file_content");
myClob.putChars( myClob.length() + 1, buffer);
We are moving to Weblogic V6.0sp1.
The getClob method on a ResultSet now returns a
weblogic.jdbc.oci.Clob which does not have a putChars method.
The best it has is getCharacterOutputStream() method
that returns a java.io.Writer which only allows me to write to the
beginning of the clob.
Question:
In Weblogic V6 how can I get a reference to a huge Clob in the database,
and just write
a little be of text to the end of it, without moving the whole thing
over the wire, twice.
Thanks.
John Xu.

Answer 1

this is a slight correction
and a second plea for help
see comments in line and below
"John Xu" <[email protected]> wrote in message
news:[email protected]...
In Weblogic V5.10sp8
I have a block of code that looks up a very large clob and appends some
text to the end of it and
writes the new larger clob back to the same row same column.
part of the code looks like this.
char[] buffer = this.getBuffer():
java.sql.ResultSet rs = this.getResultSet();
oracle.sql.CLOB myClob =
(oracle.sql.CLOB)rs.getClob("file_content");
myClob.putChars( myClob.length() + 1, buffer);
We are moving to Weblogic V6.0sp1.
The getClob method on a ResultSet now returns a
weblogic.jdbc.oci.Clob which does not have a putChars method.no, getClob does not return a
weblogic.jdbc.oci.Clob
it returns a
weblogic.jdbc.rmi.SerialClob
which is also unable to write to the end of the Clob
The best it has is getCharacterOutputStream() method
that returns a java.io.Writer which only allows me to write to the
beginning of the clob.
Question:
In Weblogic V6 how can I get a reference to a huge Clob in the database,
and just write
a little be of text to the end of it, without moving the whole thing
over the wire, twice.
Thanks.
John Xu.
here is the full method that used to work in Weblogic 5.1 sp8
in Weblogic 6.0 sp1 it now throws a ClassCastException saying
you can't cast weblogic.jdbc.rmi.SerialClob to a oracle.sql.CLOB.
I need access to the putChars method on the oracle.sql.CLOB
to write to the end of the Clob
PLEASE HELP
public void push(int tbfId, char[] buffer) throws RemoteException {
String methodName = "TicketReaderImpl.push";
String sqlFetch = "SELECT file_content FROM ticketbatchfilecontent
WHERE tbf_id = ? FOR UPDATE";
String sqlUpdate = "UPDATE ticketbatchfilecontent SET file_content =
?, update_ts=SYSDATE WHERE tbf_id = ?";
Connection conn = null;
PreparedStatement psFetch = null;
PreparedStatement psUpdate = null;
ResultSet rs = null;
OnexTransaction ot = null;
try {
ot = OnexTransaction.getInstance(methodName);
ot.begin();
conn = PersistenceManager.getDSConnection();
psFetch = conn.prepareStatement(sqlFetch);
psFetch.setInt(1,tbfId);
rs = psFetch.executeQuery();
if (rs.next()) {
oracle.sql.CLOB myClob =
(oracle.sql.CLOB)rs.getClob("file_content");
myClob.putChars( myClob.length() + 1, buffer);
psUpdate = conn.prepareStatement(sqlUpdate);
psUpdate.setClob(1,myClob);
psUpdate.setInt(2,tbfId);
psUpdate.executeUpdate();
ot.commit();
} else {
ot.commit();
throw new DatabaseException(methodName+": couldn't find
tbfId ="+tbfId);
} catch ( Exception e ) {
throw new OnexSystemException(methodName,e);
} finally {
DBUtil.close(methodName,rs);
DBUtil.close(methodName,psFetch);
DBUtil.close(methodName,psUpdate);
DBUtil.close(methodName,conn);
OnexTransaction.close(ot);