Service a Is a Utility Service That Provides Generic Data

question 9

Multiple Choice

Service A is a utility service that provides generic data access logic to a database that contains data that is periodically replicated from a shared database (1) . Because the Standardized Service Contract principle was applied to the design of Service A, its service contract has been fully standardized. The service architecture of Service A is being accessed by three service consumers. Service Consumer A accesses a component that is part of the Service A implementation by invoking it directly (2) . Service Consumer B invokes Service A by accessing its service contract (3) . Service Consumer C directly accesses the replicated database that is part of the Service A implementation (4) . You've been told that the shared database will soon be replaced with a new database product that will have new data models and new replication technology. How can the Service A architecture be changed to avoid negative impacts that may result from the replacement of the database and to establish a service architecture in which negative forms of coupling can be avoided in the future?

• A) The Contract Centralization pattern can be applied to force all service consumers to access the Service A architecture via its published service contract. This will prevent negative forms of coupling that could lead to problems when the database is replaced. The Service Abstraction principle can then be applied to hide underlying service implementation details so that future service consumers cannot be designed to access any part of the underlying service implementation.
• B) The Contract Centralization pattern can be applied to force Service Consumer C to access the Service A architecture via its published service contract. This will prevent Service Consumer A from being negatively impacted when the database is replaced in the future.
• C) The Standardized Service Contract principle can be applied to force Service Consumer B to comply to the standardized service contract of Service A. As a result, the coupling between Service Consumer B and Service A is reduced. The Logic Centralization pattern can then be applied to position the logic provided by Service A as a primary access point for the database. As a result, the component within the Service A architecture abstracts the proprietary details of the database, thereby shielding Service Consumer A (and any future service consumers) from changes made to the database.
• D) None of the above.

---

Definitions:

Gross Primary Productivity

The total rate at which an ecosystem's producers, like plants, convert solar energy into chemical energy in the form of biomass.

Photosynthesis

A method by which plants and other organisms transform light energy, often from the sun, into chemical energy that can subsequently be utilized to power the organism's functions.

Third Trophic Level

The level in an ecosystem's food chain occupied by secondary consumers, which eat primary consumers.

Herbivore

An animal that feeds on plants or algae. Also called primary consumer.