$ javac -version

javac 1.7.0_21

$ ruby --version

jruby 1.7.5.dev (1.9.3p392) 2013-06-28 fffffff on Java HotSpot(TM) 64-Bit Server VM 1.7.0_25-b15 [linux-amd64]

$ rvm --version

rvm 1.21.3 (latest-minor) by Wayne E. Seguin <wayneeseguin@gmail.com>, Michal Papis <mpapis@gmail.com> [https://rvm.io/]

...
          context 'with multi-threaded requests does a clean write' do
            it 'does not fail on parallel access (also tested on 1000.times)' do
              threads = []
              [two_facts, two_other_facts].each do |resource|
                threads << Thread.new(resource) do |_resource|
                  10.times { post(dbd_data_engine.resources_path, _resource) }
                end
              end
              threads.each { |thread| thread.join }
              read_back_graph
            end
          end

/Users/peter_v/dbd_data_engine $ rvm reinstall jruby-head
Removing /Users/peter_v/.rvm/src/jruby-head...
Removing /Users/peter_v/.rvm/rubies/jruby-head...
Installing requirements for osx_brew, might require sudo password.
Updating certificates in '/usr/local/etc/openssl/cert.pem'.
HEAD is now at a84e6d8 Rework replacement string to use Java string, target charset.
remote: Counting objects: 2640, done.
remote: Compressing objects: 100% (1322/1322), done.
remote: Total 2365 (delta 1232), reused 1872 (delta 755)
Receiving objects: 100% (2365/2365), 406.26 KiB | 332.00 KiB/s, done.
Resolving deltas: 100% (1232/1232), completed with 209 local objects.
From git://github.com/jruby/jruby
   a84e6d8..8ac5629  master     -> origin/master
 * [new branch]      jruby-6994 -> origin/jruby-6994
 + 5baf6df...e554728 pom-proposal -> origin/pom-proposal  (forced update)
 * [new branch]      truffle    -> origin/truffle
From git://github.com/jruby/jruby
 * branch            master     -> FETCH_HEAD
Updating a84e6d8..8ac5629
Fast-forward
...
Copying from repo to src path...
jruby-head - #ant jar..............
jruby-head - #ant cext..........................
Error running 'ant cext',
please read /Users/peter_v/.rvm/log/jruby-head/1377555705_ant.cext.log
cext is known to fail please report here: https://jira.codehaus.org/browse/JRUBY
jruby-head - #nailgun............................................................
jruby-head - #installing to /Users/peter_v/.rvm/rubies/jruby-head
jruby-head - #importing default gemsets, this may take time.....................
Saving wrappers to '/Users/peter_v/.rvm/wrappers/jruby-head'......................
Making gemset jruby-head pristine....
Making gemset jruby-head@global pristine....
/Users/peter_v/dbd_data_engine $ rvm use jruby-head
Using /Users/peter_v/.rvm/gems/jruby-head
/Users/peter_v/dbd_data_engine $ ruby -v
jruby 1.7.5.dev (1.9.3p392) 2013-08-27 @jruby.revision@ on Java HotSpot(TM) 64-Bit Server VM 1.6.0_51-b11-457-11M4509 [darwin-x86_64]
...
/Users/peter_v/dbd_data_engine $ rvm current
jruby-head@dbd_data_engine
/Users/peter_v/dbd_data_engine $ guard
00:28:13 - INFO - Guard is using TerminalNotifier to send notifications.
00:28:13 - INFO - Guard is using TerminalTitle to send notifications.
00:28:13 - INFO - Guard::RSpec is running
00:28:13 - INFO - Running all specs
Run options: include {:focus=>true}

All examples were filtered out; ignoring {:focus=>true}
..............................

Finished in 3.54 seconds
30 examples, 0 failures


Randomized with seed 10209

00:28:44 - INFO - Guard is now watching at '/Users/peter_v/Documents/data/github/petervandenabeele/dbd_data_engine'
...
/Users/peter_v/dbd_data_engine $ ruby -v
jruby 1.7.5.dev (1.9.3p392) 2013-08-27 @jruby.revision@ on Java HotSpot(TM) 64-Bit Server VM 1.6.0_51-b11-457-11M4509 [darwin-x86_64]