2017-05-03 19:48:29 +02:00
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---
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layout: pattern
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title: Marker Interface
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folder: marker
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permalink: /patterns/marker/
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2017-12-25 11:30:24 +02:00
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categories: Other
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2017-05-03 19:48:29 +02:00
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tags:
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- Java
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- Difficulty-Beginner
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---
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## Intent
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2017-05-23 01:38:02 +02:00
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Using empty interfaces as markers to distinguish special treated objects.
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2017-05-03 19:48:29 +02:00
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2019-12-07 20:01:13 +02:00
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## Class diagram
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2017-05-03 19:49:25 +02:00
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2017-05-03 19:48:29 +02:00
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## Applicability
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Use the Marker Interface pattern when
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2017-05-23 01:38:02 +02:00
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* you want to identify the special objects from normal objects (to treat them differently)
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* you want to mark that some object is available for certain sort of operations
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2017-05-03 19:48:29 +02:00
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## Real world examples
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2017-05-23 01:38:02 +02:00
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* [javase.8.docs.api.java.io.Serializable](https://docs.oracle.com/javase/8/docs/api/java/io/Serializable.html)
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* [javase.8.docs.api.java.lang.Cloneable](https://docs.oracle.com/javase/8/docs/api/java/lang/Cloneable.html)
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2017-05-03 19:48:29 +02:00
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## Credits
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* [Effective Java 2nd Edition by Joshua Bloch](https://www.amazon.com/Effective-Java-2nd-Joshua-Bloch/dp/0321356683)
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