Markus 5ce932ceb7 Work on #213
- properly categorize all patterns
- remove pattern list from readme
- minor fixes to readme
- removed "introduction" because its not a pattern and an error i
committed some time ago
2015-08-20 21:40:07 +02:00

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Markdown

---
layout: pattern
title: Specification
folder: specification
permalink: /patterns/specification/
categories: Behavioral
tags: Java
---
**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)