Apache Pig (Hadoop) Script + Ruby UDF

# test.rb
require 'pigudf'
require 'java'
class Myudfs < PigUdf
  outputSchema "word:chararray"
  def concat *input
    input.compact.inject(:+)
  end
end

# test.pig
register ./test.rb using jruby as myfuncs;
t = LOAD 'test.txt' USING PigStorage(',') AS (a:chararray, b:chararray);
v = FOREACH t GENERATE myfuncs.concat(a,b);
STORE v INTO 'output';

# test.txt
my, phone
any, home

$ brew install pig # OS/X
$ pig -x local test.pig
$ output/part-m-00000

Enjoy!