layout	title	folder	permalink	categories	tags
pattern	Specification	specification	/patterns/specification/	Behavioral	Java Difficulty-Beginner

Also known as

Filter, Criteria

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

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)

Related patterns

• Repository

Credits

• Martin Fowler - Specifications