/** * 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; }