/**
* Creates a new SUBSCRIBE request in the form of a <tt>ClientTransaction</tt> with the parameters
* of a specific <tt>Subscription</tt>.
*
* @param subscription the <tt>Subscription</tt> to be described in a SUBSCRIBE request
* @param dialog the <tt>Dialog</tt> with which this request should be associated
* @param expires the subscription duration of the SUBSCRIBE request to be created
* @return a new <tt>ClientTransaction</tt> initialized with a new SUBSCRIBE request which matches
* the parameters of the specified <tt>Subscription</tt> and is associated with the specified
* <tt>Dialog</tt>
* @throws OperationFailedException if the message could not be generated
*/
private ClientTransaction createSubscription(
Subscription subscription, Dialog dialog, int expires) throws OperationFailedException {
Request req = messageFactory.createRequest(dialog, Request.SUBSCRIBE);
// Address
Address toAddress = dialog.getRemoteTarget();
// no Contact field
if (toAddress == null) toAddress = dialog.getRemoteParty();
// MaxForwards
MaxForwardsHeader maxForwards = protocolProvider.getMaxForwardsHeader();
req.setHeader(maxForwards);
/*
* Create the transaction and then add the via header as recommended by
* the jain-sip documentation at
* http://snad.ncsl.nist.gov/proj/iptel/jain-sip-1.2/javadoc
* /javax/sip/Dialog.html#createRequest(String).
*/
ClientTransaction transac = null;
try {
transac = protocolProvider.getDefaultJainSipProvider().getNewClientTransaction(req);
} catch (TransactionUnavailableException ex) {
logger.error(
"Failed to create subscriptionTransaction.\n"
+ "This is most probably a network connection error.",
ex);
throw new OperationFailedException(
"Failed to create the subscription transaction",
OperationFailedException.NETWORK_FAILURE);
}
populateSubscribeRequest(req, subscription, expires);
return transac;
}
