JAXM Message Exchange Categories

 Print    E-Mail    Add Note    Add Bookmark

---

	Java APIs for XML Kick Start By Aoyon Chowdhury, Parag Choudhary
	Table of Contents
	Chapter 7.  Messaging Fundamentals

---

JAXM Message Exchange Categories

In the JAXM environment, a message exchange is essentially an exchange of SOAP-based XML documents between the businesses. They can be categorized into five types:

• Asynchronous inquiry

• Asynchronous update with acknowledgment

• Synchronous update

• Synchronous inquiry

• Fire-and-forget

We'll discuss these message categories in more detail in the following sections.

Asynchronous Inquiry

In an asynchronous inquiry, the JAXM client sends a message and does not wait for the response; see Figure 7.2. The receiver reads and processes the request and generates the reply. The reply is then sent back to the client. This reply generation and transmission is a separate process from the request receipt, and the time interval between request and response can be large, stretching into days. This type of messaging is often referred to as one-way messaging, and is possible only when messaging providers are used.

Figure 7.2. Asynchronous inquiry.

Asynchronous Update with Acknowledgment

In the asynchronous update with acknowledgment messaging scenario, the JAXM client sends the message and continues with other tasks, as seen in Figure 7.3. The receiving application reads and processes the request, and sends an acknowledgment back to the requesting client. The requesting client can then process the acknowledgment. This type of messaging also qualifies as one-way messaging, and is possible only when messaging providers are used.

Figure 7.3. Asynchronous update with acknowledgment.

Synchronous Update

In the synchronous update message exchange scenario, the requesting JAXM client sends a request and then waits until it gets a response, as seen in Figure 7.4. The response is an acknowledgment message implying the successful completion of the sent request. This type of messaging is called request-response messaging, and it's done by standalone clients.

Figure 7.4. Synchronous update.

Synchronous Inquiry

Synchronous inquiry messaging is similar to the synchronous update-messaging category. The client sends a message and waits for the response, as shown in Figure 7.5. The response message does not relate to the request per se, but is sent by the receiver to unblock the calling application. This is another type of request-response messaging done by standalone clients.

Figure 7.5. Synchronous inquiry.

Fire-and-Forget Messaging

Fire-and-forget is a messaging category in which the client sends a message and carries on with its tasks, as shown in Figure 7.6. The receiver reads and processes the request. However, no response is sent back to the requesting client.

Figure 7.6. The fire-and-forget messaging scenario.

---

 Print    E-Mail    Add Note    Add Bookmark

Top

[0672324342/ch07lev1sec1]