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I am looking for some explanation or reference info on the service provider design pattern as i came across this while studying the Grapht @defaultImplementation code (http://grepcode.com/file/repo1.maven.org/maven2/org.grouplens.grapht/grapht/0.5.0/org/grouplens/grapht/annotation/DefaultImplementation.java)

This annotation is used with annotations in the LensKit implementation as in 28:57 of this video: https://www.youtube.com/watch?v=ug_JfORWK7w

I am looking for explanation or references to learn & understand the utility of this design pattern.

Please advise

Thanks

Rookie
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Service Provider Interface: Creating Extensible Java Applications

An application is an aggregation of cohesive services. While an application offers a broader set of functionality in terms of application programming interfaces (APIs) and classes, a service provides access to some specific application functionality or feature. The service defines the interfaces for the functionality and a way to retrieve an implementation. For example, consider an application that provides a variety of information about a geographical location, such as real estate data, weather information, demographics, etc. The weather service, a part of the application, may define only the interface for retrieving the weather information (more on this example shortly).

A service provider interface (SPI) is the set of public interfaces and abstract classes that a service defines. A SPI may be represented by a single interface (type) or abstract class or a set of interfaces or abstract classes that define the service contract.

Source Service Provider Interface: Creating Extensible Java Applications

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DavidPostill
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  • I was able to go through some of the material here:[martin fowler -injection](http://martinfowler.com/articles/injection.html) and [java tutorials](http://docs.oracle.com/javase/tutorial/ext/basics/spi.html) – Rookie Aug 10 '14 at 17:18
  • The answer of Roman [in this post](http://stackoverflow.com/questions/2954372/difference-between-spi-and-api) is also a good explanation of the pattern. – Matthias Holdorf May 28 '16 at 16:43