21 lines
666 B
Markdown
21 lines
666 B
Markdown
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---
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layout: pattern
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title: Memento
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folder: memento
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categories: pattern_cat
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tags: pattern_tag
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---
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**Intent:** Without violating encapsulation, capture and externalize an
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object's internal state so that the object can be restored to this state later.
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**Applicability:** Use the Memento pattern when
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* a snapshot of an object's state must be saved so that it can be restored to that state later, and
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* a direct interface to obtaining the state would expose implementation details and break the object's encapsulation
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**Real world examples:**
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* [java.util.Date](http://docs.oracle.com/javase/8/docs/api/java/util/Date.html)
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