The JRuby community is pleased to announce the release of JRuby 1.5.0.RC1

This development cycle has been our longest cycle yet (nearly 5 months), but it also has the most fixes. It also includes many new notable features (see below). Most of our bug fixes have been more of what we consider fine-tuning, since we keep getting into smaller corner-cases of compatibility for individual Ruby methods. In that sense, we expect if you had a good experience with JRuby 1.4.0 then 1.5.0.RC1 will be a no-brainer upgrade. If you haven’t tried JRuby in a while with your application, then please give us another try. Odds are whatever issue you were having before no longer exists! And we would really like help making sure JRuby 1.5.0 final is a solid release…so please try and report back with any problems.

1.5.0.RC1 Highlights:

New native access framework designed for performance and better FFI support

Native launcher for *NIX platforms

Ant support and Rake-Ant integration

Better and better support for Windows

Multiple performance improvements for Ruby-to-Java calling, improving correctness, memory, and speed.

Embedding API improvements based on user input (JSR-223, BSF, RedBridge, etc)

Software updates: Ruby 1.8.7 standard library update, RubyGems 1.3.6, RSpec 1.3.0

ruby-debug installed by default

Many fixes for Rails 3

Various improvements to startup time

Improved performance for Object#object_id/__id__

Reduced memory use for Java class metadata and faster loading of Java classes

jar-in-jar support in the classloader

The “open4” library now works properly

jruby.jit.codeCache=dir to save jitted scripts/methods to disk in a sha1-hashed .class file

New logic for interface implementation that produces “real” classes

jruby.ji.objectProxyCache to turn off OPC for extra performance

JRuby::Synchronized module for making a class and its subclasses 100% synchronized on all calls

Miscellaneous perf improvements to core classes and minor improvements in the JIT

No more ObjectSpace during IRB

Cleaned up maven artifacts

Windows Installer fixes for x64 and Windows 7 security

Over 1250 commits since JRuby 1.4

We always appreciate community contributions. This cycle we’ve had more help than ever: David Calavera, Stephen Bannasch, Daniel Luz, Ian Dees, Koichiro Ohba, Hongli Lai, Hiroshi Nakamura, Colin Jones, Takeru Sasaki, Roger Pack, Matjaz Gregoric, Joseph LaFata, Frederic Jean, Alex Coles, Lars Westergren