如何正确添加到 JRuby on Rails 项目中的 CLASSPATH？

Question

我通过在 config/application.rb 中添加一些外部 jar 到我的 CLASSPATH 中：

require 'java'
$CLASSPATH << "#{File.dirname(__FILE__)}/../backend/src/"
Dir["#{File.dirname(__FILE__)}/../backend/lib/*.jar"].each do |jar|
   require jar
end

这在使用 Rails 服务器运行 Rails 时效果很好。加载 CLASSPATH 中的 jar。但是，运行 rake 时，未设置类路径。我该如何设置呢？特别是，我需要在加载 gem 之前设置它，因为我使用 JRClj gem，它依赖于我的 CLASSPATH 中已有的 clojure.jar。

（哦，我也尝试将代码放入environment.rb；没有帮助）

“不起作用”，我的意思是：

$ rake rspec --trace
rake aborted!
No such file to load -- /MY_CURRENT_WORKING_DIRECTORY/clojure.lang.RT
org/jruby/RubyKernel.java:1063:in `load'
/Users/pbiggar/.rvm/gems/jruby-1.6.5@jruby-clojure-combination/gems/activesupport-3.1.1/lib/active_support/dependencies.rb:234:in `load'
/Users/pbiggar/.rvm/gems/jruby-1.6.5@jruby-clojure-combination/gems/activesupport-3.1.1/lib/active_support/dependencies.rb:223:in `load_dependency'
/Users/pbiggar/.rvm/gems/jruby-1.6.5@jruby-clojure-combination/gems/activesupport-3.1.1/lib/active_support/dependencies.rb:640:in `new_constants_in'
/Users/pbiggar/.rvm/gems/jruby-1.6.5@jruby-clojure-combination/gems/activesupport-3.1.1/lib/active_support/dependencies.rb:639:in `new_constants_in'
/Users/pbiggar/.rvm/gems/jruby-1.6.5@jruby-clojure-combination/gems/activesupport-3.1.1/lib/active_support/dependencies.rb:223:in `load_dependency'
/Users/pbiggar/.rvm/gems/jruby-1.6.5@jruby-clojure-combination/gems/activesupport-3.1.1/lib/active_support/dependencies.rb:234:in `load'
/Users/pbiggar/.rvm/gems/jruby-1.6.5@jruby-clojure-combination/gems/rake-0.9.2.2/lib/rake/rake_module.rb:25:in `load_rakefile'
/Users/pbiggar/.rvm/gems/jruby-1.6.5@jruby-clojure-combination/gems/rake-0.9.2.2/lib/rake/default_loader.rb:6:in `load'
/Users/pbiggar/.rvm/gems/jruby-1.6.5@jruby-clojure-combination/gems/rake-0.9.2.2/lib/rake/application.rb:569:in `load_imports'
/Users/pbiggar/.rvm/gems/jruby-1.6.5@jruby-clojure-combination/gems/rake-0.9.2.2/lib/rake/application.rb:508:in `raw_load_rakefile'
/Users/pbiggar/.rvm/gems/jruby-1.6.5@jruby-clojure-combination/gems/rake-0.9.2.2/lib/rake/application.rb:82:in `load_rakefile'
/Users/pbiggar/.rvm/gems/jruby-1.6.5@jruby-clojure-combination/gems/rake-0.9.2.2/lib/rake/application.rb:133:in `standard_exception_handling'
/Users/pbiggar/.rvm/gems/jruby-1.6.5@jruby-clojure-combination/gems/rake-0.9.2.2/lib/rake/application.rb:81:in `load_rakefile'
/Users/pbiggar/.rvm/gems/jruby-1.6.5@jruby-clojure-combination/gems/rake-0.9.2.2/lib/rake/application.rb:65:in `run'
/Users/pbiggar/.rvm/gems/jruby-1.6.5@jruby-clojure-combination/gems/rake-0.9.2.2/lib/rake/application.rb:133:in `standard_exception_handling'
/Users/pbiggar/.rvm/gems/jruby-1.6.5@jruby-clojure-combination/gems/rake-0.9.2.2/lib/rake/application.rb:63:in `run'
/Users/pbiggar/.rvm/gems/jruby-1.6.5@jruby-clojure-combination/gems/rake-0.9.2.2/bin/rake:33:in `(root)'
org/jruby/RubyKernel.java:1063:in `load'
/Users/pbiggar/.rvm/gems/jruby-1.6.5@jruby-clojure-combination/bin/rake:19:in `(root)'

Answer 1

发生这种情况是因为我使用的 gem 使用 import 而不是 java_import，点击 JRUBY 错误 3797。更多详细信息，请参见： JRuby：导入、包含、java_import 与include_class。

问题中的代码是正确的。