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Steps to Run Ruby from Java
- Include the jruby-complete-<version>.jar dependency on the classpath for your project. This is really all that's needed to run jruby code
- Use BSF, JSR223 or jruby core to "embed" ruby inside java (run ruby from java). See the Jruby wiki for more.
- Try using jruby-complete-<version>.jar to run a simple ruby
script. This should fail because jruby-complete won't be able to
find the sass gem.
java -jar jruby-complete-1.6.7.jar -S sass_helper.rb
- To use ruby gems from java, first package the gem into a jar file
mkdir sass-gems java -jar jruby-complete-1.6.7.jar -S gem install -i ./sass-gems sass --no-rdoc --no-ri jar cf sass-gems.jar -C sass-gems .
- Verify that the jar contains the correct gem directory structure.
jar -tf sass-gems.jar | head
- Now, the sasshelper.rb script should run successfully as long as it
it can find the jar containing the sass gem
java -jar jruby-complete-1.6.7.jar -S sass_helper.rb # will still fail java -jar jruby-complete-1.6.7.jar -rsass-gems.jar -S sass_helper.rb
- Publish the custom created jar to a repo so that we can use it as a maven dependency
mvn deploy:deploy-file -DgroupId=com.upgradingdave -DartifactId=sass-gem -Dversion=3.1.17 -Dpackaging=jar -Dfile=sass-gems.jar -Durl=http://dev.upgradingdave.com/artifactory/ext-release-local -DrepositoryId=upgradingdave-release
- Add com.upgradingdave:sass-gems:3.1.17 to pom and then test by calling sasshelp.rb from RubyExample.java main method
- For convenience, use gem maven plugin to automatically retrieve gems as maven artifacts from torquebox rubygems maven proxy repository
Embedding ruby inside java: https://github.com/jruby/jruby/wiki/RedBridge
Package gems into a jar: http://blog.nicksieger.com/articles/2009/01/10/jruby-1-1-6-gems-in-a-jar
Maven proxy that automatically converts ruby gems to maven dependencies: http://rubygems-proxy.torquebox.org/
Ruby Version Manager (very convenient for installing and using jruby, along with other ruby implementations) https://rvm.io/