310ae50248
* Adding support for maven assembly plugin to generate executable jar with all dependencies in built * Merge branch 'master' into issue-989 # Conflicts: # abstract-document/pom.xml # pom.xml * Adding maven assemly plugin for projects with name A * Update in format as per checkstyle, i.e. Spcae in place of tab with size of 2 * batch set - 2 having all project with B and C * issue-989 d-e-f * fixing eip pom and adding g-h-i-l-m-n Skipping naked object as it seems it doesn't have main method, will consider this at end * Adding for O and P projects Skipping Object-Mother as we don't have main method for same. * Final batch
layout, title, folder, permalink, categories, tags
| layout | title | folder | permalink | categories | tags | ||
|---|---|---|---|---|---|---|---|
| pattern | Service Locator | service-locator | /patterns/service-locator/ | Architectural |
|
Intent
Encapsulate the processes involved in obtaining a service with a strong abstraction layer.
Class diagram
Applicability
The service locator pattern is applicable whenever we want to locate/fetch various services using JNDI which, typically, is a redundant and expensive lookup. The service Locator pattern addresses this expensive lookup by making use of caching techniques ie. for the very first time a particular service is requested, the service Locator looks up in JNDI, fetched the relevant service and then finally caches this service object. Now, further lookups of the same service via Service Locator is done in its cache which improves the performance of application to great extent.
Typical Use Case
- When network hits are expensive and time consuming
- Lookups of services are done quite frequently
- Large number of services are being used
Consequences
- Violates Interface Segregation Principle (ISP) by providing pattern consumers with an access to a number of services that they don't potentially need.
- Creates hidden dependencies that can break the clients at runtime.