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Designing a Service's Interaction Layer

Interaction Layer

Processing Layer

JM

Business

Web

Web

S

Logic

Service

Service

Client

Endpoint

Figure 3.7

Asynchronous Interaction Between Client and Service

Figure 3.8 shows how the travel agency service might implement this interac 

tion, and Code Example 3.16 shows the actual code that might be used.

Travel Agency 

Processing

Client

JMS Queue/Topic

Service Endpoint

Layer

Request travel reservation

Delegate request to JMS

after validation

Return correlation ID

Request

Inquire 

Option 1: Polling

Status/result

Option 2: Callback

Request result

Figure 3.8

Travel Agency Service Interaction