all index.md files renamed to README.md for more compatibility with github

specification/README.md

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+---
+layout: pattern
+title: Specification
+folder: specification
+permalink: /patterns/specification/
+categories: Behavioral
+tags:
+ - Java
+ - Difficulty-Beginner
+---
+
+## Intent
+Specification pattern separates the statement of how to match a
+candidate, from the candidate object that it is matched against. As well as its
+usefulness in selection, it is also valuable for validation and for building to
+order
+
+![alt text](./etc/specification.png "Specification")
+
+## Applicability
+Use the Specification pattern when
+
+* you need to select a subset of objects based on some criteria, and to refresh the selection at various times
+* you need to check that only suitable objects are used for a certain role (validation)
+
+## Credits
+
+* [Martin Fowler - Specifications](http://martinfowler.com/apsupp/spec.pdf)