Appending to a large object

Hi,

sorry for bothering you again.

I want to append some data to a LargeObject, but I could not find out
how to do that. When I simply do

ResultSet rs = queryStmt.executeQuery();
try {
if (rs.next()) {
int oid = rs.getInt(1); // or wherever my Id is
LargeObject obj = lobj.open(oid);
System.out.println("SIze is " + obj.size();
OutputStream os = obj.getOutputStream();
os.write(...); // here I want to append to the existing stream
obj.close();
dbConn.commit();
}
} catch (SQLException e) {
dbConn.rollBack();
} finally {
rs.close();
}

It is not appended to the stream but overwritten from the beginning.
The LargeObject defines some variables SEEK_SET, SEEK_END, SEEK_CUR
that seem to be useful for my purpose; however I could not find the
method to use them.

Can you give me a hint how I can append to an existing LargeObject
(using the OutputStream interface)?

Ciao

Ole

P.S. Is there a Java standard API documentation (javadoc-converted)
of the extensions (es. LargeObject handling) available?