Rake “no such file to load — java” even when `whic

Question

I am a Ruby noob (rube?) and am having trouble configuring my environment to get rake to build something with a Java dependency.

I run

$ PATH=/tmp/jruby-dodge:"$PATH" rake

and get

/opt/local/bin/ruby -S rspec spec/contextual_spec.rb
/opt/local/lib/ruby/vendor_ruby/1.8/rubygems/custom_require.rb:31:in `gem_original_require': no such file to load -- java (LoadError)
        from /opt/local/lib/ruby/vendor_ruby/1.8/rubygems/custom_require.rb:31:in `require'
        from /Users/msamuel/work/igrigorik/contextual/lib/contextual/contextual.rb:1
        from /opt/local/lib/ruby/vendor_ruby/1.8/rubygems/custom_require.rb:31:in `gem_original_require'
        from /opt/local/lib/ruby/vendor_ruby/1.8/rubygems/custom_require.rb:31:in `require'
        from /Users/msamuel/work/igrigorik/contextual/lib/contextual.rb:2
        from /opt/local/lib/ruby/vendor_ruby/1.8/rubygems/custom_require.rb:31:in `gem_original_require'
        from /opt/local/lib/ruby/vendor_ruby/1.8/rubygems/custom_require.rb:31:in `require'
        from /Users/msamuel/work/igrigorik/contextual/spec/contextual_spec.rb:1
        from /opt/local/lib/ruby/gems/1.8/gems/rspec-core-2.8.0/lib/rspec/core/configuration.rb:698:in `load'
        from /opt/local/lib/ruby/gems/1.8/gems/rspec-core-2.8.0/lib/rspec/core/configuration.rb:698:in `load_spec_files'
        from /opt/local/lib/ruby/gems/1.8/gems/rspec-core-2.8.0/lib/rspec/core/configuration.rb:698:in `map'
        from /opt/local/lib/ruby/gems/1.8/gems/rspec-core-2.8.0/lib/rspec/core/configuration.rb:698:in `load_spec_files'
        from /opt/local/lib/ruby/gems/1.8/gems/rspec-core-2.8.0/lib/rspec/core/command_line.rb:22:in `run'
        from /opt/local/lib/ruby/gems/1.8/gems/rspec-core-2.8.0/lib/rspec/core/runner.rb:80:in `run_in_process'
        from /opt/local/lib/ruby/gems/1.8/gems/rspec-core-2.8.0/lib/rspec/core/runner.rb:69:in `run'
        from /opt/local/lib/ruby/gems/1.8/gems/rspec-core-2.8.0/lib/rspec/core/runner.rb:10:in `autorun'
        from /opt/local/bin/rspec:19
rake aborted!
/opt/local/bin/ruby -S rspec spec/contextual_spec.rb failed

Tasks: TOP => default => spec
(See full trace by running task with --trace)

The PATH=/tmp/jruby-dodge:... makes sure that which ruby actually resolves to a symlink to /opt/local/bin/jruby.

Is "no such file to load -- java" related to jruby at all? java -version emits java version "1.6.0_29" so I don't think there is a failure to start up a JVM.

When using rake to build something with Java dependencies for use under jruby, does it matter whether rake is running under jruby or ruby? If so, how do I specify that?

Answer 1

It looks like rvm lets me juggle multiple rubies.

Installing RVM explains how to install it.

rvm install jruby

makes sure rvm knows about jruby.

rvm use jruby

updates the environment so that ruby means jruby.

Gems seem to be installed per-flavor of ruby.