24 lines
1.0 KiB
Markdown
24 lines
1.0 KiB
Markdown
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---
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layout: pattern
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title: Chain of responsibility
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folder: chain-of-responsibility
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categories: pattern_cat
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tags: pattern_tag
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---
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**Intent:** Avoid coupling the sender of a request to its receiver by giving
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more than one object a chance to handle the request. Chain the receiving
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objects and pass the request along the chain until an object handles it.
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**Applicability:** Use Chain of Responsibility when
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* more than one object may handle a request, and the handler isn't known a priori. The handler should be ascertained automatically
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* you want to issue a request to one of several objects without specifying the receiver explicitly
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* the set of objects that can handle a request should be specified dynamically
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**Real world examples:**
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* [java.util.logging.Logger#log()](http://docs.oracle.com/javase/8/docs/api/java/util/logging/Logger.html#log%28java.util.logging.Level,%20java.lang.String%29)
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* [Apache Commons Chain](https://commons.apache.org/proper/commons-chain/index.html)
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