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ServiceLocator in Pet Store

Edy Yu
Ranch Hand

Joined: Nov 21, 2000
Posts: 264
I am browsing Pet Store 1.3.1 from Sun.
Any body can give me a reason why they use one service locator for web tier and the other for Business/EJB tier. The only difference I noticed is the web tier service locator "cache" the references.

<i><br />Sun Certified Programmer for Java 2 Platform (SCJP)<br />Sun Certified Developer for Java 2 Platform (SCJD)<br />Sun Certified Web Component Developer for Java2 Platform, Enterprise Edition (SCWCD)<br />Sun Certified Business Component Developer for Java2 Platform, Enterprise Edition (SCBCD)<br />Sun Certified Enterprise Architect for J2EE (SCEA)<br />IBM Certified Enterprise Developer, WebSphere Studio V5.0<br /></i>
Lasse Koskela

Joined: Jan 23, 2002
Posts: 11962
Could it be because of (some of) the following:
a) they wanted to demonstrate two different ways of implementing the service locator pattern.
b) they didn't have the time/interest to write a configurable service locator (cache on/off)
I'm just guessing here...

Author of Test Driven (2007) and Effective Unit Testing (2013) [Blog] [HowToAskQuestionsOnJavaRanch]
Chris Mathews
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Joined: Jul 18, 2001
Posts: 2712
c) They wanted to decouple the Web and EJB tiers. Therefore making it much easier to locate them on separate JVMs or even separate physical boxes.
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subject: ServiceLocator in Pet Store
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