Converted /documentation/ruby-from-other-languages/to-ruby-from-java/index.html to markdown.

Author: postmodern

documentation/ruby-from-other-languages/to-ruby-from-java/index.html

@@ -0,0 +1,56 @@
+---
+layout: page
+title: To Ruby From Java
+---
+
+Java is mature. It’s tested. And it’s fast (contrary to what the
+anti-Java crowd may still claim). It’s also quite verbose. Going from
+Java to Ruby, expect your code size to shrink down considerably. You can
+also expect it to take less time to knock together quick prototypes.
+
+### Similarities
+
+As with Java, in Ruby,...
+
+* Memory is managed for you via a garbage collector.
+* Objects are strongly typed.
+* There are public, private, and protected methods.
+* There are embedded doc tools (Ruby’s is called RDoc). The docs
+  generated by rdoc look very similar to those generated by javadoc.
+
+### Differences
+
+Unlike Java, in Ruby,...
+
+* You don’t need to compile your code. You just run it directly.
+* There are several different popular third-party GUI toolkits.
+  Ruby users can try [WxRuby][1], [FXRuby][2], [Ruby-GNOME2][3], or the
+  bundled-in Ruby Tk for example.
+* You use the `end` keyword after defining things like classes, instead
+  of having to put braces around blocks of code.
+* You have `require` instead of `import`.
+* All member variables are private. From the outside, you access
+  everything via methods.
+* Parentheses in method calls are usually optional and often omitted.
+* Everything is an object, including numbers like 2 and 3.14159.
+* There’s no static type checking.
+* Variable names are just labels. They don’t have a type associated with
+  them.
+* There are no type declarations. You just assign to new variable names
+  as-needed and they just “spring up” (i.e. `a = [1,2,3]` rather than
+  `int[] a = {1,2,3};`).
+* There’s no casting. Just call the methods. Your unit tests should tell
+  you before you even run the code if you’re going to see an exception.
+* It’s `foo = Foo.new( "hi")` instead of `Foo foo = new Foo( "hi" )`.
+* The constructor is always named “initialize” instead of the name of
+  the class.
+* You have “mixin’s” instead of interfaces.
+* YAML tends to be favored over XML.
+* It’s `nil` instead of `null`.
+* `==` and `equals()` are handled differently in Ruby. Use `==` when you
+  want to test equivalence in Ruby (`equals()` is Java). Use `equal?()`
+  when you want to know if two objects are the same (`==` in Java).
+
+[1]: http://wxruby.rubyforge.org/wiki/wiki.pl 
+[2]: http://www.fxruby.org/ 
+[3]: http://ruby-gnome2.sourceforge.jp/