1 files changed, 10 insertions, 3 deletions
diff --git a/Gemfile b/Gemfile
index 51ff10a..747bc71 100644
--- a/Gemfile
+++ b/Gemfile
@@ -2,8 +2,15 @@
 
 source 'https://rubygems.org'
 
-gemspec :name => 'json'
-gemspec :name => 'json_pure'
-gemspec :name => 'json-java'
+case ENV['JSON']
+when 'ext', nil
+  if ENV['RUBY_ENGINE'] == 'jruby'
+    gemspec :name => 'json', :path => 'java'
+  else
+    gemspec :name => 'json'
+  end
+when 'pure'
+  gemspec :name => 'json_pure'
+end
 
 gem 'simplecov'