Advanced Queuing - Oracle

Enqueuing and Dequeuing Of Messages
"select empty_clob() from dual");
rset1 = (OracleResultSet) clob_stmt0.executeQuery ();
try
{
if (rset1.next())
{
c1 = (oracle.sql.CLOB)rset1.getClob(1);
}
if (c1 == null)
{
System.out.println("select empty_clob() from dual failed");
}
}
catch (Exception ex)
{
System.out.println("Exception2 during select from dual " + ex);
ex.printStackTrace();
}
id=i+1;
mStr = "Message #" + id;
sPayl.setId(new BigDecimal(id));
sPayl.setTrailer(new BigDecimal(id));
sPayl.setSubject(mStr);
sPayl.setData(b1);
sPayl.setCdata(c1);
/* Set Object Payload data */
sPayload.setPayloadData(sPayl);
/* Enqueue the message */
queue1.enqueue(eq_option, adt_msg);
System.out.println("Enqueued Message: " + id );
smsgid = adt_msg.getMessageId();
/*
* Note: The message is initially enqueued with an EMPTY BLOB and CLOB
* After enqueuing the message, we need to get the lob locators and
* then populate the LOBs
*/
blob_stmt = (OracleCallableStatement)db_conn.prepareCall(
"SELECT user_data FROM qt_adt where msgid = ?");
blob_stmt.setBytes(1,smsgid);
rset2 = (OracleResultSet) blob_stmt.executeQuery ();
try
{
Oracle Advanced Queuing by Example A-59