java-design-patterns/layers/README.md

---
layout: pattern
title: Layers
folder: layers
permalink: /patterns/layers/
pumlformat: svg
categories: Architectural
tags:
 - Java
 - Difficulty-Intermediate
 - Spring
---

## Intent
Layers is an architectural style where software responsibilities are
 divided among the different layers of the application.

![alt text](./etc/layers.png "Layers")

## Applicability
Use the Layers architecture when

* you want clearly divide software responsibilities into different parts of the program
* you want to prevent a change from propagating throughout the application
* you want to make your application more maintainable and testable

## Credits

* [Pattern Oriented Software Architecture Vol I-V](http://www.amazon.com/Pattern-Oriented-Software-Architecture-Volume-Patterns/dp/0471958697)
#84 Added pattern description 2015-08-15 21:44:08 +03:00			`---`
			`layout: pattern`
			`title: Layers`
			`folder: layers`
			`permalink: /patterns/layers/`
Work on #190: urm/puml updates * added pumlid where it was missing and possible * removed pumlid where it generated a bad image * regenerated some incorrect puml's * added 'left to right direction' puml prefix to some diagrams to improve the automatic layouting 2017-03-25 22:07:10 +01:00			`pumlformat: svg`
Work on #213 - properly categorize all patterns - remove pattern list from readme - minor fixes to readme - removed "introduction" because its not a pattern and an error i committed some time ago 2015-08-20 21:40:07 +02:00			`categories: Architectural`
Categorize and tag all patterns #213 2015-12-28 15:52:44 +02:00			`tags:`
			`- Java`
			`- Difficulty-Intermediate`
			`- Spring`
#84 Added pattern description 2015-08-15 21:44:08 +03:00			`---`

Use headings instead of bold text in index.md #238 2016-01-03 21:14:30 +01:00			`## Intent`
			`Layers is an architectural style where software responsibilities are`
#84 Added pattern description 2015-08-15 21:44:08 +03:00			`divided among the different layers of the application.`

			`![alt text](./etc/layers.png "Layers")`

Use headings instead of bold text in index.md #238 2016-01-03 21:14:30 +01:00			`## Applicability`
			`Use the Layers architecture when`
#84 Added pattern description 2015-08-15 21:44:08 +03:00
corrected typos 2017-08-31 01:50:33 +05:30			`* you want clearly divide software responsibilities into different parts of the program`
#84 Added pattern description 2015-08-15 21:44:08 +03:00			`* you want to prevent a change from propagating throughout the application`
			`* you want to make your application more maintainable and testable`
Work on #226, moved POSA reference and some J2EE design pattern references 2015-09-24 12:23:02 +05:30
Use headings instead of bold text in index.md #238 2016-01-03 21:14:30 +01:00			`## Credits`
Work on #226, moved POSA reference and some J2EE design pattern references 2015-09-24 12:23:02 +05:30
			`* [Pattern Oriented Software Architecture Vol I-V](http://www.amazon.com/Pattern-Oriented-Software-Architecture-Volume-Patterns/dp/0471958697)`