JRuby

JRuby describes a Ruby interpreter for the Java Virtual Machine( JVM). JRuby is a completely in Java implemented interpreter, and makes - comparable among other things with Scala, Groovy, BeanShell, Jython, Jacl - the use possible of the JVM on basis of the programming language Ruby.

The background of JRuby is the interoperability of the two languages Ruby and Java. Thus then the concepts of the object-oriented, procedural and functional paradigms as well as the concurrent programming are executable on the JVM. The language range of Ruby is almost completely implemented by JRuby and is subject to a constant advancement by the team Charles Nutter and Thomas Enebo. These provide concerning JRuby also again and again extensive information. Thus in 2009 a version of JRuby executable on the software platform for mobile devices - Android - was presented.

The platform-independent JRuby is available in December 2009 in the version 1.4. In addition, a compiler is available that translates Ruby classes (version 1.8) into Java classes.

JRuby realizes as runtime interpreter the possibility of mapping the properties of the programming language Ruby on the JVM. Thus the extensive Java libraries can be embedded into the Ruby program code. This mechanism is also described as "Subclassing Java". By the use of JRuby however also Java programs can call programs implemented in Ruby. Thus, JRuby provides the opportunity to develop additional transparent Ruby-on-Rails applications in addition to integrating existing Java applications and their libraries.

A clear advantage of JRuby is that the program code is reduced with same functionality in relation to Java. Corresponding measurements of the performance of the executable program code confirm JRuby considerable advantages in comparison to the use of the MRI environment (Matz Ruby Interpreter). JRuby is thus also an excellent runtime environment for web applications under Ruby on Rails. In this context, however, it is equally worth mentioning the Java Virtual Machine, which achieves a very high performance in the execution of JRuby code with the HotSpot technology under current aspects.