Recently we posted a list of tutorials to help you get started with NetBeans Ruby and Rails. Another way to get started is by watching the NetBeans Ruby screencasts, starring Tor Norbye and Roman Strobl, and produced by Cindy Church. These screencasts provide an overview of the features of NetBeans Ruby, including the Ruby Editor and Debugger, and also provide scenarios for creating Ruby and Rails applications. Sit back, relax, and enjoy.

Creating Ruby and Rails Applications

• Using Ruby Support to Create a Weblog
• Mixing Java and Ruby Development

Using the Ruby Editor

• Editing Ruby Code
• Using Code Completion
• Using Hints and Quick Fixes

Testing and Debugging

• Writing Unit Tests
• Debugging Ruby Code

When I started learning Ruby, all of the code samples that I looked at used positional arguments in the constructor, such as with the following code:

  def initialize(id, type, price)
    @id, @type, @price = id, type, price
  end

By positional arguments, I mean that the first argument must pass the id, the second must pass type, and the third must pass price. Having worked with C and Java, this feels very familiar, and so that is how I did it in my own code. However, when I posted my code samples to the dev@ruby.netbeans.org alias, a few developers suggested that I use a hash, like in the following code.

  def initialize(attributes)
    @id = attributes['id']
    @type = attributes['type']
    @price = attributes['price'].to_f
  end

I can see some advantages of using a hash instead of requiring arguments in a certain order. For one, with positional arguments, there is the possibility of passing the values in the wrong order. Another advantage of a hash is that if you add more attributes to a class, the constructor's signature does not change.

There was a bit of a debate about which version to use. Some developers like the constructor with positional arguments because it clearly documents the intent of the class. Others feel that keyword arguments, along with RDoc, make the code more clear than depending on argument ordering to convey meaning. Comparing the two types of method invocations, I have to agree that the hash seems easier to read.

  Item.new 'id' => 'ABC', type' => 'book',  'price' => 17

  Item.new 'ABC', 'book', 23

How about you? What are your preferences? Do you carry it even further? Would you ever consider doing something like this?

  def initialize(&block)
    instance_eval &block
  end

  item = Item.new do
    self.id = 'ABC'
    ...
  end

Do you know of scenarios where it might be appropriate to use code like this?

  def initialize(attributes)
    @attributes = attributes.with_indifferent_access
  end
 
  def method_missing(symbol, *args)
    @attributes[symbol] ? @attributes[symbol] : super
  end

Charles Nutter has blogged about how to extend Class with a field-initializing 'new' method. Jay Fields posted in his blog code forcreating constructors that can take either positional arguments or a hash. For someone starting out with Ruby, I find these latter methods a bit uncomfortable, but it does save a bit of finger work. What do you think?

Do you need help getting started with NetBeans Ruby? If so, we have three learning trails to get you going. Our first trail gives you a whirlwind tour of the NetBeans Ruby and Ruby on Rails environment. The second trail provides the nuts and bolts for creating a basic Ruby on Rails application. The third trail is an all-in-one lesson for working with Ruby and Java applications. You can start at whatever trail best meets your needs.

Trail 1: Getting Started

• Installing and Configuring Ruby Support, Databases, and GlassFish
• Getting Started With Ruby and Rails

Trail 2: Creating a Ruby on Rails Application

• Creating a Ruby Weblog in 10 Minutes
• Building Relationships Between Rails Models
• Using Ajax with Ruby on Rails

Trail 3: Integrating Ruby and Java Development

• Mixing Java and Ruby Applications

If you haven't tried calling Java classes from a JRuby application yet, here is a simple code snippet to get you started. Paste the following code into the Ruby shell (JRuby IRB), press Enter, and a small desktop app opens (To open the Ruby shell in the NetBeans IDE, choose Ruby > Other > Ruby Shell (IRB) from the main menu). This code is an updated version of an example in the JRuby and the Java Platform article.

Note: A current known bug causes the JRuby IRB to report an ExitSecurityException, this bug does not affect the output.

include Java

import javax.swing.JFrame
import javax.swing.JLabel
import javax.swing.JPanel
import javax.swing.JButton
import java.awt.BorderLayout

frame = JFrame.new
panel = JPanel.new
panel.layout = BorderLayout.new
panel.background = java.awt.Color::white
frame.get_content_pane.add(panel)
frame.default_close_operation = JFrame::EXIT_ON_CLOSE
button = JButton.new "Click Me"
text = JLabel.new "I'm a Simple Program"

panel.add(BorderLayout::CENTER, text)
panel.add(BorderLayout::SOUTH, button)

class Click
    include java.awt.event.ActionListener

    def initialize(button, text)
        @button, @text = button, text
        @click_me_mode = true
    end

    def actionPerformed(event)
        source = event.source
        if (source == @button)
            if (@click_me_mode)
                @text.text = "Button Clicked"
                @button.text = "Click Again"
                @click_me_mode = false
            else
                @text.text = "I'm a Simple Program"
                @button.text = "Click Me"
                @click_me_mode = true
            end
        end
    end
end

button.add_action_listener(Click.new(button, text))
frame.title = "Example"
frame.pack
frame.visible = true 

The IRB is a nice way to test out your code. However, with the NetBeans IDE, it is just as easy to test out code in a scratch program. To see what I mean, right-click in the NetBeans Projects window and choose New > Project. In the New Project wizard, select Ruby in the Categories pane, select Ruby Application in the Projects pane, and click Next. Name the project Scratch (or whatever you want) and click Finish. The main.rb file opens in the editor.

Replace the contents of the main.rb file with the code sample. Then click the Run Main Project button in the main toolbar (the green arrow) to run the application.

As you can see by the following screenshot, the advantage of testing your code in a scratch project as opposed to using the IRB is that you get syntax coloring and all the other wonderful NetBeans Ruby editing features.

To learn about the editing features, see the NetBeans Ruby Editing wiki page, or look at Tor's screenshot of the week entries, such as Ruby Screenshot of the Week #18: Errors and Snippets (as of today, he is up to screenshot #23). We are also working on a getting started guide that will cover some of the editing features. Last, you can watch Roman's Editing screencast.

There are a couple of FAQs that you might find helpful

1. How to Call Java From Ruby
2. How Can I Access Java From the JRuby IRB?

You also might want to check out the Swing with JRuby: Developing a Desktop Application with the JRuby and Java Swing APIs tutorial that was written by Sun campus ambassador Teera Kanokkanjanarat.

We are redesigning the documentation lists and learning trails to include more than just written articles and tutorials. We are asking for your help in coming up with a design that works best for you. Below are links to four designs. Please take a look at each of the designs in terms of identifying the media type for a title.

• v4
• v2
• v3
• v1

Of the four, which page (v1, v2, v3, or v4) do you think makes it easiest to find what you are looking for in the desired media? Please briefly explain the benefits of that page and why you prefer it over the others.

Which page (v1, v2, v3, or v4) do you think is the worst for finding information in the desired media? Please briefly explain why you rate it last.

So as to not bias other people's opinions, please do not post your feedback as a comment. Instead, send your response to nbdocsfeedback@emailias.com

Thank you very much for your time. Hopefully your input will make it easier to find the right docs at the right time.

The other day, Tor Norbye sent us an email listing some NetBeans Ruby navigation shortcuts, which we thought we'd highlight in the blog. We did a little further research on the subject and also list here some favorite user shortcuts that we undercovered.

(For a complete list of NetBeans Ruby Keyboard Shortcuts, see Ruby Shortcuts).

Navigation Shortcuts

Navigation is important - jumping between files and their tests, or between Rails actions and views. Here are some navigation shortcuts:

• If you're in a controller file, and realize you need to modify its corresponding view, press Ctrl-Shift-A (Command-Shift-A on the Mac) to jump to it. Press again to go in the opposite direction.
• Similarly, if you're in a Rails controller file (for example) and want to go edit its unit test, hit Ctrl-Shift-T (Command-Shift-T on the Mac) to jump to it - and again to jump back.

User Favorite Shortcuts

Here are some more frequently used shortcuts.

NetBeans Shortcuts

You can download a shortcut card that lists the highlights of the NetBeans IDE 6.0 keyboard shortcuts and code templates. In the NetBeans IDE, choose Help > Keyboard Shortcuts Card from the main menu. Similarly, you can view the shortcuts online from the NetBeans IDE 6.0 Keyboard Shortcuts Specification.

Teera Kanokkanjanarat is a Sun campus ambassador who recently contributed the tutorial Swing with JRuby: Developing a Desktop Application with the JRuby and Java Swing APIs. Here we interview Teera to find out more about his interest in NetBeans Ruby.

I've been working as a freelance software developer for about 8 years ever since finishing high school. My work mainly focuses on the web platform with various technologies ranging from Java, ASP.NET, PHP, and recently I got started on Ruby and Rails. Since November 2006, I've been hired by Sun as a campus ambassador at Simon University in British Columbia, Vancouver, where I'm completing my degree in Computing Science and Business Administration.

What is your interest in Ruby?

Coming from the strongly-typed language world of Java and C#, I find the flexibility and dynamic of the Ruby language to be very interesting. I believe that the productivity of developers has a heavy impact on the cost of software projects. I often find that I waste time waiting for the project to compile and re-deploy to web or application servers. So that's the first thing I found really appealing when I started working with the Ruby and Rails framework. Ruby seems to gain a lot of momentum on the web platform with the Rails framework. Now I'm more interested in the future of Ruby as a rich client on the desktop.

How did you learn Ruby?

I started out on Hal Fulton's The Ruby Way book to learn the Ruby language itself and the Ruby way of doing things. I often watch screencasts and vodcasts for techniques on learning Rails. I'm also a member of the Vancouver Ruby and Rails user group, where I attend monthly meetings. This is an interesting group; as a Java guy, I learn so much from others who work with Ruby on a daily basis.

What do you like and dislike about Ruby?

The Ruby language itself is beautiful. There are not many programming languages that are as intuitive and give me that "wow this is cool stuff!" sort of thrill. Of course, this is also because of Ruby's coding conventions and key principles.

I actually did a small experiment re-creating one of my old, small Java-based web projects with Ruby on Rails. I found that the entire project on RoR actually contains fewer lines of code than that in the previous version's configuration files!

In my opinion, performance and deployment are still the key issues of Ruby. JRuby and other initiatives are really aiming on these two issues.

How has NetBeans helped you build Ruby apps?

I tried RadRails, TextMate, and InstantRails. Yet, I like Netbeans Ruby support the most, especially in code editing, the Ruby debugger, and the auto-complete capability. Netbeans is tightly integrated with JRuby as well.

Tell us about the NetBeans Ruby app you are currently building?

What was your favorite experience as a Sun ambassador?

Meeting with people! I made a lot of friends from around the world through this program. I also learned a lot from talking to people when I do evangelizing work, whether it's a tech demo or a presentation at a user group. Nothing beats learning from those who do real work out there in the field.

What are some things you like to do outside school and work?

I started a small coffee shop back when I was 19 and opened up a day-spa with my sister about two years ago. Both of them are in Thailand. So, I'm helping my sister run them remotely.

Where do you see yourself in five years?

Completing my degree is my first priority (it has been delayed several times due to my work). After finishing my term at Sun at the end of this year, I'll be joining Business Objects as a software developer. In the next five years, I might do another startup if there some good ideas come along, but things change, you never know.