java-design-patterns/hexagonal/README.md

---
layout: pattern
title: Hexagonal Architecture
folder: hexagonal
permalink: /patterns/hexagonal/
pumlformat: svg
categories: Architectural
language: en
tags:
 - Decoupling
---

## Also known as

* Ports and Adapters
* Clean Architecture
* Onion Architecture

## Intent
Allow an application to equally be driven by users, programs, automated test or batch scripts, and to be developed and tested in isolation from its eventual run-time devices and databases.

## Class diagram
![Hexagonal Architecture class diagram](./etc/hexagonal.png)

## Applicability
Use Hexagonal Architecture pattern when

* When the application needs to be independent of any frameworks
* When it is important that the application highly maintainable and fully testable

## Tutorials

* [Build Maintainable Systems With Hexagonal Architecture](http://java-design-patterns.com/blog/build-maintainable-systems-with-hexagonal-architecture/)

## Real world examples

* [Apache Isis](https://isis.apache.org/) builds generic UI and REST API directly from the underlying domain objects

## Credits

* [Alistair Cockburn - Hexagonal Architecture](http://alistair.cockburn.us/Hexagonal+architecture)
Add readme and class diagram 2016-04-10 21:22:40 +03:00			`---`
			`layout: pattern`
			`title: Hexagonal Architecture`
			`folder: hexagonal`
			`permalink: /patterns/hexagonal/`
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`
Add readme and class diagram 2016-04-10 21:22:40 +03:00			`categories: Architectural`
fix: Fixed pages showing up in wrong language (#1752) * Fix languages * Missed change for version number * Add language field for presentation * Revert change in README for double buffer Co-authored-by: Jackie Nim <=> 2021-05-19 10:49:05 -06:00			`language: en`
Add readme and class diagram 2016-04-10 21:22:40 +03:00			`tags:`
https://github.com/iluwatar/java-design-patterns-web/issues/8 Update pattern categories and tags 2019-12-13 21:09:28 +02:00			`- Decoupling`
Add readme and class diagram 2016-04-10 21:22:40 +03:00			`---`

Add alias name for the pattern 2016-04-10 21:49:40 +03:00			`## Also known as`
https://github.com/iluwatar/java-design-patterns-web/issues/8 Update pattern categories and tags 2019-12-13 21:09:28 +02:00
Markdown fix 2016-05-22 09:33:50 +03:00			`* Ports and Adapters`
			`* Clean Architecture`
			`* Onion Architecture`
Add alias name for the pattern 2016-04-10 21:49:40 +03:00
Add readme and class diagram 2016-04-10 21:22:40 +03:00			`## Intent`
			`Allow an application to equally be driven by users, programs, automated test or batch scripts, and to be developed and tested in isolation from its eventual run-time devices and databases.`

#1113 Link uml-reverse-mapper created class diagrams to readme, where needed 2019-12-07 20:01:13 +02:00			`## Class diagram`
Add readme and class diagram 2016-04-10 21:22:40 +03:00			`![Hexagonal Architecture class diagram](./etc/hexagonal.png)`

			`## Applicability`
			`Use Hexagonal Architecture pattern when`

Work on Hexagonal Architecture presentation 2016-11-12 22:44:08 +02:00			`* When the application needs to be independent of any frameworks`
			`* When it is important that the application highly maintainable and fully testable`
Add readme and class diagram 2016-04-10 21:22:40 +03:00
Link Hexagonal Architecture pattern to corresponding blog entry 2016-11-06 12:26:03 +02:00			`## Tutorials`
https://github.com/iluwatar/java-design-patterns-web/issues/8 Update pattern categories and tags 2019-12-13 21:09:28 +02:00
Link Hexagonal Architecture pattern to corresponding blog entry 2016-11-06 12:26:03 +02:00			`* [Build Maintainable Systems With Hexagonal Architecture](http://java-design-patterns.com/blog/build-maintainable-systems-with-hexagonal-architecture/)`

Add readme and class diagram 2016-04-10 21:22:40 +03:00			`## Real world examples`

Add presentation link to README.md 2016-11-13 11:37:49 +02:00			`* [Apache Isis](https://isis.apache.org/) builds generic UI and REST API directly from the underlying domain objects`
Add readme and class diagram 2016-04-10 21:22:40 +03:00
			`## Credits`

			`* [Alistair Cockburn - Hexagonal Architecture](http://alistair.cockburn.us/Hexagonal+architecture)`