Term
You want centralized, common processing across requests, such as checking the data-encoding scheme of each request, logging information about each request, or compressing an outgoing response |
|
Definition
|
|
Term
You want pre and postprocessing components loosely coupled with core request-handling services to facilitate unobtrusive addition and removal. |
|
Definition
|
|
Term
* You want pre and postprocessing components independent of each other and self contained to facilitate reuse. |
|
Definition
|
|
Term
Centralizes control (FC) Loosely coupled (use the deployment descriptor to add and remove) Reusable |
|
Definition
|
|
Term
Declarative and flexible configuration Information sharing is inefficient Related Patterns Front Controller |
|
Definition
|
|
Term
* You want to avoid duplicate control logic. |
|
Definition
|
|
Term
You want to apply common logic to multiple requests. You want to separate system processing logic from the view You want to centralize controlled access points into your system |
|
Definition
|
|
Term
Centralizes control (IF) Improves reusability |
|
Definition
|
|
Term
You want to keep Views/presentation, Controls/business logic, and Models/data access separate. |
|
Definition
|
|
Term
Allows multiple view types for the same info Decouples presentation, business logic, and data access components |
|
Definition
|
|
Term
* You want clients to access components in other tiers to retrieve and update data. * You want to reduce remote requests across the network. |
|
Definition
|
|
Term
Reduces network traffic Simplifies remote object and remote interface Introduces stale transfer objects and concurrency issues Reduces coupling between presentation and business tiers (BD, SL) |
|
Definition
|
|
Term
* You want to hide the details of service creation, reconfiguration, and invocation retries from the clients. |
|
Definition
|
|
Term
* You want to minimize coupling between clients and the business services, thus hiding the underlying implementation details of the service, such as lookup and access. * You want to translate network exceptions into application or user exceptions. |
|
Definition
|
|
Term
Reduces coupling between presentation and business tiers (TO, SL) Translates business service exceptions Exposes a simpler, uniform interface to the business tier Introduces an additional layer Hides remoteness |
|
Definition
|
|
Term
* You want to use the JNDI API to look up and use business components, such as enterprise beans and JMS components, and services such as data sources. |
|
Definition
|
|
Term
* You want to centralize and reuse the implementation of lookup mechanisms for J2EE application clients. |
|
Definition
|
|
Term
* You want to avoid performance overhead related to initial context creation and service lookups. * You want to reestablish a connection to a previously accessed enterprise bean instance, using its Handle object. |
|
Definition
|
|
Term
Provides uniform service access to clients Reduces coupling between presentation and business tiers (TO, BD) Improves client performance by caching service handles |
|
Definition
|
|