1. Using JRuby on Rails With Sun GlassFish Enterprise Server
Introduction to JRuby and Rails on Sun GlassFish Enterprise Server
JRuby on Rails, the Sun GlassFish Enterprise Server v3, and the GlassFish v3 Gem
Installation and Configuration of JRuby
To Install JRuby and Rails from Update Center
To Install JRuby as Standalone
Enterprise Server v3 JRuby Container Configuration
Configuring JRuby Container Through Asadmin CLI
Configuring JRuby Runtime Pool
Configuring JRuby Container Through Administration Console
To Configure JRuby Container from Administration Console
Creating a Simple Rails Application
To Create the hello Application
To Create the Controller and the View
To Pass Data From the Controller to the View
To Use Rails Without a Database
Deploying and Running a Rails Application
To Deploy the Rails Application as a Directory
Accessing Java Libraries From a Rails Application
To Create the Rails Application That Accesses Java Libraries
To Create the Views That Display the Images Generated by Java2D Code
To Add Java2D Code to a Rails Controller
To Run a Rails Application That Uses Java 2D Code
Monitor Rails Applications on Enterprise Server v3
Monitoring for JRuby Container
Viewing JRuby Container Statistics
To Install the GlassFish v3 Gem
To Run a Rails Application on GlassFish v3 Gem
To Deploy and Run the Database-Backed Web Application
Creating and Deploying a Simple Rails Application with Warbler
One of the main functions of Rails is to make a quick-and-easy task of creating an application that accesses a database. This section shows you the steps to create a simple application that accesses a book database using MySQL. You should have already installed JRuby, Rails, and the required Gems.
Download and install MySQL database server:
Configure the server according to the MySQL documentation, including entering a root password.
Start the server.
Create or select a directory for creating a database-backed Rails application.
Change to that directory.
Create and configure a application template to use the MySQL database:
jruby -S rails books -d mysql
Change to the books directory that you just created.
Replace mysql with jdbcmysql.
Open the config/database.yml file in a text editor.
When prompted, enter your MySQL root password under the development heading in the database.yml file.
Change back to the books directory if you are not already there.
Create the database by running the following command:
jruby -S rake db:create
After the database creation is complete, you should see output similar to the following:
** Execute db:create
The rake command invokes the Rake tool. The Rake tool builds applications by running Rake files, which are written in Ruby and provide instructions for building applications.
Create the scaffold and the Book model for the application:
jruby script/generate scaffold book title:string author:string isbn:string description:text
When you run the script/generate command, you specify the name of the model, the names of the columns, and the types for the data contained in the columns.
A scaffold is the set of code that Rails generates to handle database operations for a model object, which is Book in this case. The scaffold consists of a controller and some views that allow users to perform the basic operations on a database, such as viewing the data, adding new records, and editing records. Rails also creates the model object when generating the scaffold.
Create the database tables:
jruby -S rake db:migrate
When Rails is finished creating the tables, you should see output similar to the following:
CreateBooks: migrated (0.1322ms) =========
If you need to reset the database later, you can run the following command:
jruby —S rake db:reset