19 lines
660 B
Markdown
19 lines
660 B
Markdown
---
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layout: pattern
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title: Specification
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folder: specification
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categories: pattern_cat
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tags: pattern_tag
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---
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**Intent:** Specification pattern separates the statement of how to match a
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candidate, from the candidate object that it is matched against. As well as its
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usefulness in selection, it is also valuable for validation and for building to
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order
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**Applicability:** Use the Specification pattern when
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* you need to select a subset of objects based on some criteria, and to refresh the selection at various times
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* you need to check that only suitable objects are used for a certain role (validation) |