22 lines
1018 B
Markdown
22 lines
1018 B
Markdown
|
---
|
||
|
|
layout: pattern
|
||
|
|
title: Prototype
|
||
|
|
folder: prototype
|
||
|
|
categories: pattern_cat
|
||
|
|
tags: pattern_tag
|
||
|
|
---
|
||
|
|
|
||
|
|
**Intent:** Specify the kinds of objects to create using a prototypical
|
||
|
|
instance, and create new objects by copying this prototype.
|
||
|
|
|
||
|
|
|
||
|
|
|
||
|
|
**Applicability:** Use the Prototype pattern when a system should be independent of how its products are created, composed and represented; and
|
||
|
|
|
||
|
|
* when the classes to instantiate are specified at run-time, for example, by dynamic loading; or
|
||
|
|
* to avoid building a class hierarchy of factories that parallels the class hierarchy of products; or
|
||
|
|
* when instances of a class can have one of only a few different combinations of state. It may be more convenient to install a corresponding number of prototypes and clone them rather than instantiating the class manually, each time with the appropriate state
|
||
|
|
|
||
|
|
**Real world examples:**
|
||
|
|
|
||
|
|
* [java.lang.Object#clone()](http://docs.oracle.com/javase/8/docs/api/java/lang/Object.html#clone%28%29)
|