Asynchronous Messages 

Use

The Adapter Framework offers a transactional concept that provides a secure solution for quality of service Exactly Once for the sender and receiver adapter. In error situations in the sender channel, potential duplicates can be identified and deleted. In the receiver channel, administrator action is usually required to correct an error status.

Prerequisites

With respect to asynchronous messages, an adapter:

●      Cannot send a response message in the receiver direction

●      Cannot expect a response message in the sender direction

The following prerequisite applies to the receiver direction:

●      The adapter must disclose which types of acknowledgment messages it does not support.

●      The adapter must ensure that the supported acknowledgment messages are returned asynchronously or synchronously to the Integration Server.

Acknowledgment messages are not currently supported for the sender direction. For later changes, see SAP Note 1004000.

To implement an Exactly Once delivery, the adapter uses the following services:

MessageIDMapper

This service enables you to map an external message ID to an XI message ID. The mapping is saved in the database and can be executed in the same LUW (logical unit of work) as the Adapter Framework messaging service.

More information: Generating, Persisting, and Mapping a Message ID

The Adapter Framework expects the adapter to provide an external message ID. Either the message ID of the external protocol is used or message IDs are generated using algorithms (for example, hash).

An example of an ID of an external protocol is the JMS message ID.

In the example adapter, it is generated from the following elements: file name, file directory, and time of change.

TransactionManager

AS Java provides the functions of the package com.sap.transaction. com.sap.transaction.TxManager is used to control LUWs using different components (service, ejb, and jca).

Features

Message processing involves various steps in the sender and receiver direction:

●      Transactions for the Asynchronous Sender Direction

●      Transactions for the Asynchronous Receiver Direction

●      For more information about acknowledgments, see Creating Acknowledgment Messages.