Mixing programming languages and using each one where it provides the most power is becoming a common practice. Java's multiple JVM-compatible language projects like Groovy, Scala, Jython and JRuby are a testament to this.
In this entry, Charles Nutter takes a close a look a JRuby, Java's implementation for running Ruby a top Java's JVM. So why does Charles consider JRuby an important project ? In a nutshell:
JRuby takes a decade of Java dogma and turns it on its head. JRuby isn't about Java, it's about taking the best of the Java platform and using it to improve Ruby. It's about me and others working relentlessly, writing Java so you don't have to. It's about giving Ruby access to one of the best VMs around, to one of the largest collections of libraries in the world, to a pool of talented engineers who've written this stuff a dozen times over. Sure there's crap in the Java world. Sure the Java elite took power in the late 90s and started to jam a bunch of nonsense down our throats. Sure the language has aged a bit. That's all peripheral. JRuby makes it possible to filter out and take advantage of the good parts of the Java world without writing a single line of Java.
JRuby is not going away. More people try JRuby every day. As long as Rubyists who know "the way", who have learned how to create beautiful APIs and DSLs, who serve as the stars, the leaders of the Ruby community, setting standards for others to follow...as long as those people try to marginalize JRuby, treat it like a pariah, or convince others to do the same....it will only get worse.
Read Charle's complete entry on JRuby 'The Elephant':