Reliable RPC for DCOM Wrapper

Writing a Client

All methods for reliable RPC are available on the interface object. See Standard Wrapper Properties for details. The methods are

  • RPCService.Reliable (put and get)
  • RPCService.ReliableCommit
  • RPCService.ReliableRollback
  • RPCService.MessageID
  • RPCService.get_StatusOfMessage

Create Broker object and interface object:

// DCOM Wrapper Object
MAILClass    mail;
mail.Logon();

Disable reliable RPC:

mail.Reliable = mail.RELIABLE_OFF;

Enable reliable RPC with AUTO_COMMIT or CLIENT_COMMIT: 

mail.Reliable = mail.RELIABLE_AUTO_COMMIT;
mail.Reliable = mail.RELIABLE_CLIENT_COMMIT;

The first RPC message:

mail.SENDMAIL("mail receiver", "Subject 1", "Text 1");

Check the status: get the message ID first and use it to retrieve the status: 

String messageID = mail.MessageID;
String messageStatus = mail.get_StatusOfMessage(messageID);
System.out.println("Status: " + messageStatus + ", id: " + messageID);

The second RPC message:

mail.SENDMAIL("mail receiver", "Subject 2", "Text 2");

Commit the two messages:

mail.ReliableCommit();

Check the status again for the same message ID:

messageStatus = mail.get_StatusOfMessage(messageID);
System.out.println("Status: " + messageStatus + ", id: " + messageID);

The third RPC message.

mail.SENDMAIL("mail receiver", "Subject 3", "Text 3");

Check the status: get the new message ID and use it to retrieve the status: 

messageID = mail.MessageID();
messageStatus = mail.get_StatusOfMessage(messageID);
System.out.println("Status: " + messageStatus + ", id: " + messageID);

Roll back the third message and check status:

mail.ReliableRollback();
messageStatus = mail.getStatusOfMessage(messageID);
System.out.println("Status: " + messageStatus + ", id: " + messageID);
mail.logoff();

Limitations

  • All program calls that are called in the same transaction (CLIENT_COMMIT) must be in the same IDL library.

  • It is not allowed to switch from CLIENT_COMMIT to AUTO_COMMIT in a transaction.

  • Messages (IDL programs) must have only IN parameters.

Writing a Server

Not applicable.