Weblogism

Find a Class in Jars (II)

This one is a follow-up to this post, finding a class in jars under a certain folder. But this time, it is obviously in Ruby:

require 'java'


def scanDir(className, dirname='C:')
  begin
    Dir.foreach(dirname) do |filename|
      next if (filename == "." or filename == "..")
      if File.directory?(filename)
        scanDir className, filename
      elsif File.fnmatch("**.jar", filename)
        scanJar(className, File.join(dirname, filename))
      end 
    end
  rescue SystemCallError
    $stderr.print "IO failed: " + $!
  end
end


def scanJar(className, jarfile)
  entries = java.util.jar.JarFile.new(jarfile).entries
  entries.each do |entry| 
    if entry.getName().to_s.index(className) != nil 
      puts "#{jarfile}: #{entry}\n"
    end
  end
end


if ARGV.size == 2
  scanDir ARGV[0], ARGV[1]
else 
  puts "Usage: jruby search_jar.rb <class_name> <directory>"
end

You then call it as follows:

jruby search_jar.rb MyNiceStub C:\application_server\lib

Edit: Ideally, something like Rake’s FileList would make finding the jar in subfolders a trivial task…