Tasks to compile the jruby project into a standalone jar

gistfile1.rb

# Compile the jruby project into a standalone jar, doc refers to
# https://github.com/jruby/jruby/wiki/StandaloneJarsAndClasses
namespace :pkg do
  
  PGEM_FILES = []
  PLIB_FILES = []
  PROJECT_JAR = "package/project_name.jar"
  JRUBY_JAR = "jruby-complete-1.6.1.jar"
  BOOTSTRAP = "jar-bootstrap.rb"
   
  desc "compile and build the package"
  task :build => [:pkg_dir, :copy_gems, :compile_lib, :project_jar]
    
  desc "destroy the built package"
  task :clean do
    rm_rf "package"
  end
  
  desc "run the built package"
  task :run => :build do
    sh "java -jar #{PROJECT_JAR}"
  end
  
  # # # # # # # # # # # # # # # # # # # # # # # # # # # 
    
  # the "package" directory task
  directory "package"
  task :pkg_dir => "package"
  
  # the copy gems task
  GEM_FILES = FileList['gems/**/*.*']
  GEM_FILES.each do |gemf|
    pgemf = File.join("package", gemf)
    pgemdir = File.dirname(pgemf)
    mkdir_p(pgemdir) unless File.exist?(pgemdir)
    file pgemf => gemf do
      cp(gemf, pgemf)
      raise "Fail to copy #{gemf}" if not File.exist?(pgemf)
    end
    PGEM_FILES << pgemf
  end
  task :copy_gems => PGEM_FILES
 
  # the compile lib task
  LIB_FILES = FileList['lib/**/*.*']
  LIB_FILES.each do |libf|
    plibf = File.join("package", libf)
    plibdir = File.dirname(plibf)
    mkdir_p(plibdir) unless File.exist?(plibdir)
    if File.extname(libf) == '.rb'
      plibf = plibf.sub(".rb", ".class")
      file plibf => libf do
        sh "jrubyc \"#{libf}\" --target package/"
        raise "Fail to compile #{libf}" if not File.exist?(plibf)
      end
    else
      file plibf => libf do
        cp(libf, plibf)
        raise "Fail to copy #{libf}" if not File.exist?(plibf)
      end
    end
    PLIB_FILES << plibf
  end
  task :compile_lib => PLIB_FILES
  
  # the project jar task
  file PROJECT_JAR => [JRUBY_JAR, BOOTSTRAP] do
    cp(JRUBY_JAR, PROJECT_JAR)
    sh "jar ufe #{PROJECT_JAR} org.jruby.JarBootstrapMain #{BOOTSTRAP}"
  end
  task :project_jar => PROJECT_JAR 

end