This document introduces the Grails framework. It discusses that Grails is an open source web application framework built on Groovy and follows conventions over configuration. The document outlines the history, components, advantages and disadvantages of Grails. It also lists some prominent websites that use Grails like Netflix and Sky TV Guide. Finally, it discusses the future of Grails including separation from application servers and evolution of GORM for NoSQL databases.

1. Inroduction to Grails
Hiten Pratap Singh
hitenpratap99@gmail.com
http://github.com/hitenpratap

2. Agenda
●
What is Grails?
●
Why Grails?
●
History of Grails
●
Technology stack of Grails
●
Directory structure of Grails
●
Main Components of Grails
●
Pros and Cons of Grails
●
WebSites using Grails

3. Agenda
●
Future of Grails
●
References

4. What is Grails?
●
Grails is an open source web application framework
●
uses the Groovy programming language
●
following the "coding by convention" paradigm
●
providing a stand-alone development environment and
hiding much of the configuration detail
●
Also following DRY(don't repeat yourself) paradigm
●
Grails is highly inspired from Ruby on Rails web framework
like DRY and COC principles.

5. Why Grails?
●
According to its official websites-
– Grails is Robust
– Grails is Dynamic
– Grails is Rapid
●
Most important reasion to use it is that it runs on JVM and
leverages all plus points of JAVA
●
Any Java developer can learn it very quickly rather than
migrate to other framework for RAD development.
●
Grails is agile and based on plugins means any
functionality can be attach/detach to it very easily.

6. Why Grails?
●
Grails is actually Spring and Hibernate plus trending
concepts from Ruby on Rails like DRY and COC etc.
●
It's very dynamic ecosystem
●
Very active developer community
●
Grails removes the need to add configuration in XML files

7. History of Grails
●
Grails was previously known as 'Groovy on Rails
●
Work began in July 2005, with the 0.1 release on March
29, 2006
●
Graeme Rocher is project head and creator of Grails
framework.
●
Grails is made by G2One, later acquired by Spring Source.
●
It developed due to need of RAD framework for JAVA
programmer community like Ruby on Rails in Ruby
programmer community.

8. Technology stack of Grails

9. Directory structure of Grails
%PROJECT_HOME%
+ grails-app
+ conf --->
location of configuration
artifacts
+ hibernate --->

10. Directory structure of Grails
+ util --->
location of special utility
classes
+ views --->
location of views
+ layouts --->

11. Main components of Grails
Actually as a MVC framework there are only three main
component of Grails and they are-
●
Model(domain)
●
Controller
●
View
But there are many other essential components of Grails
which makes it different from others like-
●
Services

12. Main components of Grails
●
Taglib
●
Plugins
●
Templating

13. Pros and cons of using Grails
What are the advantages?
●
It provides a rapid development cycle.
●
The framework offers a range of plug-ins to make your
development simple.
●
You can see the changes by hitting the refresh button.
●
Dynamic configuration feature. Therefore, you can change
the configuration without server restart.
●
The setup process is very simple. Therefore, you should
be able to start building an app in an hour.

14. Pros and cons of using Grails
What are the disadvantages?
●
Interpreted languages increase weight and that directly
affects the run time.
●
It works with GORM but not with any other ORMs.
●
Developers generally declare variables with “def” which is
equivalent to “object”. It’s very hard to maintain.
●
You have to deal with runtime language.

15. WebSites Using Grails
Folowing websites are currently using Grails-
●
Netflix Asgard - https://github.com/Netflix/asgard
●
NOW TV - http://nowtv.com
●
Vodafone Music - http://music.vodafone360.com/gb/en
●
Sky TV Guide - http://tv.sky.com/
and many more.......
source:
http://grails.org

16. Future of Grails
●
Grails 3.0 will separate Grails from the traditional
application server and extend Grails’ reach to allow for the
development of lightweight, asynchronous applications.
●
Grails’ persistence technology GORM has also been
evolving beyond the traditional relational database, with
implementations for NoSQL databases now available.
●
GORM will continue to be an important technology for us
as enterprise data fabrics evolve.
Source:http://www.cacoethes.co.uk/blog/groovyandgrails/where-next-for-grails

17. References
●
http://grails.org
●
http://grails.org/websites
●
http://www.cacoethes.co.uk/blog/groovyandgrails/where-next-fo
●
http://en.wikipedia.org/wiki/Grails_(framework)

18. Any questions?

19. Thank You.......