are you doing somthing like this . if not try it .
...
...
//your code
stmt = conn.createStatement();
rs1 = stmt.executeQuery("select * from mytable where mycolumn = "+myvar
+" for update");
if(rs1.next())
{
my_clob = ((OracleResultSet)rs1).getCLOB(yourcolumnindex);
insertClob(my_clob,myclobvalue);
}
stmt.execute("commit");
rs1.close();
stmt.close();
...
...
public void insertClob(oracle.sql.CLOB clob,
String value) throws Exception
{
try
{
OutputStream outstream = clob.getAsciiOutputStream();
outstream.flush();
outstream.write(value.getBytes());
outstream.close();
}catch(Exception e){e.printStackTrace();}
}