ruby - jruby モジュールがインストールされているかどうかを確認するにはどうすればよいですか?

Question

私はRuby、Rails、Jrubyにとても慣れていません。しかし、私は本当にtabula-extractorを試してみたいと思っています。確認方法がわかりませんが、正しくインストールしたと思います。これは、最初の提案に基づいた私のスクリプトです。

#!/usr/bin/jruby

require 'tabula'

pdf_file_path = "page19.pdf"
outfilename = "page19.csv"

out = open(outfilename, 'w')

extractor = Tabula::Extraction::ObjectExtractor.new(pdf_file_path, :all )
extractor.extract.each do |pdf_page|
  pdf_page.spreadsheets.each do |spreadsheet|
    out << spreadsheet.to_csv
    out << "\n\n"
  end
end
out.close

これを実行すると、次のようになります。

./tabula.rb:10: uninitialized constant Tabula (NameError)
    from ./tabula.rb:3:in `require'
    from ./tabula.rb:3

それをどのように解釈するかさえわかりません。Tabula が見つからないと言っているのではなく、"NameError" があるというだけです。extractor = Tabula::Extraction::ObjectExtractor.new(pdf_file_path, :all )

明らかな何かが欠けていると確信しています。tabula-extractor が本当にインストールされているかどうかさえわかりません。私は走っjruby -S gem install tabula-extractorてこれを取り戻しました：

JRuby limited openssl loaded. http://jruby.org/openssl
gem install jruby-openssl for full support.
System.java:-2:in `arraycopy': java.lang.ArrayIndexOutOfBoundsException
    from DefaultResolver.java:111:in `makeTime'
    from DefaultResolver.java:277:in `create'
    from DefaultResolver.java:317:in `handleScalar'
    from DefaultResolver.java:435:in `orgHandler'
    from DefaultResolver.java:455:in `node_import'
    from org/yecht/ruby/DefaultResolver$s_method_1_0$RUBYINVOKER$node_import.gen:65535:in `call'
    from CachingCallSite.java:146:in `call'
    from RubyLoadHandler.java:39:in `handle'
    from Parser.java:300:in `addNode'
    from DefaultYAMLParser.java:676:in `yyparse'
    from Parser.java:290:in `yechtparse'
    from Parser.java:284:in `parse'
    from YParser.java:152:in `load'
    from org/yecht/ruby/YParser$s_method_0_1$RUBYINVOKER$load.gen:65535:in `call'
    from JavaMethod.java:630:in `call'
    from DynamicMethod.java:186:in `call'
    from CachingCallSite.java:309:in `cacheAndCall'
    from CachingCallSite.java:148:in `call'
    from CallOneArgNode.java:57:in `interpret'
    from LocalAsgnNode.java:123:in `interpret'
    from NewlineNode.java:104:in `interpret'
    from InterpretedMethod.java:180:in `call'
    from DefaultMethod.java:174:in `call'
    from CachingCallSite.java:309:in `cacheAndCall'
    from CachingCallSite.java:148:in `call'
    from CallOneArgNode.java:57:in `interpret'
    from LocalAsgnNode.java:123:in `interpret'
    from NewlineNode.java:104:in `interpret'
    from BlockNode.java:71:in `interpret'
    from InterpretedMethod.java:180:in `call'
    from DefaultMethod.java:174:in `call'
    from CachingCallSite.java:309:in `cacheAndCall'
    from CachingCallSite.java:148:in `call'
    from CallOneArgNode.java:57:in `interpret'
    from NewlineNode.java:104:in `interpret'
    from RescueNode.java:199:in `executeBody'
    from RescueNode.java:118:in `interpretWithJavaExceptions'
    from RescueNode.java:110:in `interpret'
    from InterpretedMethod.java:180:in `call'
    from DefaultMethod.java:174:in `call'
    from CachingCallSite.java:309:in `cacheAndCall'
    from CachingCallSite.java:148:in `call'
    from FCallOneArgNode.java:36:in `interpret'
    from InstAsgnNode.java:95:in `interpret'
    from NewlineNode.java:104:in `interpret'
    from BlockNode.java:71:in `interpret'
    from EnsureNode.java:96:in `interpret'
    from BeginNode.java:83:in `interpret'
    from NewlineNode.java:104:in `interpret'
    from WhenOneArgNode.java:36:in `whenSlowTest'
    from WhenOneArgNode.java:46:in `when'
    from CaseNode.java:133:in `interpret'
    from NewlineNode.java:104:in `interpret'
    from InterpretedBlock.java:373:in `evalBlockBody'
    from InterpretedBlock.java:346:in `yield'
    from InterpretedBlock.java:303:in `yield'
    from Block.java:194:in `yield'
    from YieldNode.java:112:in `interpret'
    from NewlineNode.java:104:in `interpret'
    from BlockNode.java:71:in `interpret'
    from InterpretedBlock.java:373:in `evalBlockBody'
    from InterpretedBlock.java:346:in `yield'
    from InterpretedBlock.java:303:in `yield'
    from Block.java:194:in `yield'
    from RubyKernel.java:1251:in `loop_1_9'
    from org/jruby/RubyKernel$s_method_0_0$RUBYFRAMEDINVOKER$loop_1_9.gen:65535:in `call'
    from CachingCallSite.java:299:in `cacheAndCall'
    from CachingCallSite.java:117:in `callBlock'
    from CachingCallSite.java:132:in `callIter'
    from FCallNoArgBlockNode.java:32:in `interpret'
    from NewlineNode.java:104:in `interpret'
    from InterpretedMethod.java:160:in `call'
    from DefaultMethod.java:166:in `call'
    from CachingCallSite.java:299:in `cacheAndCall'
    from CachingCallSite.java:117:in `callBlock'
    from CachingCallSite.java:122:in `call'
    from CallNoArgBlockNode.java:64:in `interpret'
    from NewlineNode.java:104:in `interpret'
    from BlockNode.java:71:in `interpret'
    from InterpretedMethod.java:242:in `call'
    from DefaultMethod.java:198:in `call'
    from CachingCallSite.java:339:in `cacheAndCall'
    from CachingCallSite.java:197:in `callBlock'
    from CachingCallSite.java:202:in `call'
    from RubyClass.java:819:in `call'
    from DynamicMethod.java:194:in `call'
    from WrapperMethod.java:62:in `call'
    from CachingCallSite.java:329:in `cacheAndCall'
    from CachingCallSite.java:188:in `call'
    from FCallTwoArgNode.java:38:in `interpret'
    from LocalAsgnNode.java:123:in `interpret'
    from NewlineNode.java:104:in `interpret'
    from BlockNode.java:71:in `interpret'
    from EnsureNode.java:96:in `interpret'
    from InterpretedMethod.java:242:in `call'
    from DefaultMethod.java:198:in `call'
    from CachingCallSite.java:339:in `cacheAndCall'
    from CachingCallSite.java:197:in `callBlock'
    from CachingCallSite.java:202:in `call'
    from CallTwoArgBlockPassNode.java:62:in `interpret'
    from NewlineNode.java:104:in `interpret'
    from BlockNode.java:71:in `interpret'
    from InterpretedMethod.java:283:in `call'
    from DefaultMethod.java:214:in `call'
    from CachingCallSite.java:359:in `cacheAndCall'
    from CachingCallSite.java:237:in `callBlock'
    from CachingCallSite.java:252:in `callIter'
    from CallThreeArgBlockNode.java:64:in `interpret'
    from NewlineNode.java:104:in `interpret'
    from BlockNode.java:71:in `interpret'
    from InterpretedMethod.java:262:in `call'
    from DefaultMethod.java:206:in `call'
    from CachingCallSite.java:349:in `cacheAndCall'
    from CachingCallSite.java:228:in `call'
    from FCallThreeArgNode.java:40:in `interpret'
    from NewlineNode.java:104:in `interpret'
    from InterpretedBlock.java:373:in `evalBlockBody'
    from InterpretedBlock.java:346:in `yield'
    from InterpretedBlock.java:303:in `yield'
    from Block.java:194:in `yield'
    from RubyIO.java:1106:in `open'
    from RubyKernel.java:283:in `open'
    from org/jruby/RubyKernel$s_method_0_2$RUBYFRAMEDINVOKER$open.gen:65535:in `call'
    from DynamicMethod.java:198:in `call'
    from CachingCallSite.java:339:in `cacheAndCall'
    from CachingCallSite.java:197:in `callBlock'
    from CachingCallSite.java:212:in `callIter'
    from FCallTwoArgBlockNode.java:34:in `interpret'
    from NewlineNode.java:104:in `interpret'
    from IfNode.java:119:in `interpret'
    from IfNode.java:119:in `interpret'
    from NewlineNode.java:104:in `interpret'
    from BlockNode.java:71:in `interpret'
    from InterpretedMethod.java:221:in `call'
    from DefaultMethod.java:190:in `call'
    from CachingCallSite.java:329:in `cacheAndCall'
    from CachingCallSite.java:188:in `call'
    from CallTwoArgNode.java:59:in `interpret'
    from InstAsgnNode.java:95:in `interpret'
    from NewlineNode.java:104:in `interpret'
    from RescueNode.java:199:in `executeBody'
    from RescueNode.java:118:in `interpretWithJavaExceptions'
    from RescueNode.java:110:in `interpret'
    from BeginNode.java:83:in `interpret'
    from NewlineNode.java:104:in `interpret'
    from BlockNode.java:71:in `interpret'
    from InterpretedMethod.java:242:in `call'
    from DefaultMethod.java:198:in `call'
    from CachingCallSite.java:339:in `cacheAndCall'
    from CachingCallSite.java:197:in `callBlock'
    from CachingCallSite.java:202:in `call'
    from RubyClass.java:819:in `call'
    from DynamicMethod.java:194:in `call'
    from CachingCallSite.java:329:in `cacheAndCall'
    from CachingCallSite.java:188:in `call'
    from CallTwoArgNode.java:59:in `interpret'
    from DAsgnNode.java:110:in `interpret'
    from NewlineNode.java:104:in `interpret'
    from BlockNode.java:71:in `interpret'
    from InterpretedBlock.java:373:in `evalBlockBody'
    from InterpretedBlock.java:346:in `yield'
    from InterpretedBlock.java:303:in `yield'
    from Block.java:194:in `yield'
    from RubyArray.java:1630:in `eachCommon'
    from RubyArray.java:1637:in `each'
    from org/jruby/RubyArray$i_method_0_0$RUBYFRAMEDINVOKER$each.gen:65535:in `call'
    from CachingCallSite.java:299:in `cacheAndCall'
    from CachingCallSite.java:117:in `callBlock'
    from CachingCallSite.java:122:in `call'
    from CallNoArgBlockNode.java:64:in `interpret'
    from NewlineNode.java:104:in `interpret'
    from BlockNode.java:71:in `interpret'
    from InterpretedMethod.java:221:in `call'
    from DefaultMethod.java:190:in `call'
    from CachingCallSite.java:329:in `cacheAndCall'
    from CachingCallSite.java:188:in `call'
    from CallTwoArgNode.java:59:in `interpret'
    from NewlineNode.java:104:in `interpret'
    from BlockNode.java:71:in `interpret'
    from RescueNode.java:199:in `executeBody'
    from RescueNode.java:118:in `interpretWithJavaExceptions'
    from RescueNode.java:110:in `interpret'
    from BeginNode.java:83:in `interpret'
    from NewlineNode.java:104:in `interpret'
    from InterpretedBlock.java:373:in `evalBlockBody'
    from InterpretedBlock.java:346:in `yield'
    from InterpretedBlock.java:303:in `yield'
    from Block.java:194:in `yield'
    from RubyArray.java:1630:in `eachCommon'
    from RubyArray.java:1637:in `each'
    from org/jruby/RubyArray$i_method_0_0$RUBYFRAMEDINVOKER$each.gen:65535:in `call'
    from CachingCallSite.java:299:in `cacheAndCall'
    from CachingCallSite.java:117:in `callBlock'
    from CachingCallSite.java:122:in `call'
    from CallNoArgBlockNode.java:64:in `interpret'
    from NewlineNode.java:104:in `interpret'
    from BlockNode.java:71:in `interpret'
    from InterpretedMethod.java:139:in `call'
    from DefaultMethod.java:158:in `call'
    from CachingCallSite.java:289:in `cacheAndCall'
    from CachingCallSite.java:108:in `call'
    from VCallNode.java:85:in `interpret'
    from NewlineNode.java:104:in `interpret'
    from IfNode.java:119:in `interpret'
    from IfNode.java:119:in `interpret'
    from NewlineNode.java:104:in `interpret'
    from BlockNode.java:71:in `interpret'
    from InterpretedMethod.java:180:in `call'
    from DefaultMethod.java:174:in `call'
    from CachingCallSite.java:309:in `cacheAndCall'
    from CachingCallSite.java:148:in `call'
    from CallSpecialArgNode.java:67:in `interpret'
    from NewlineNode.java:104:in `interpret'
    from BlockNode.java:71:in `interpret'
    from CaseNode.java:138:in `interpret'
    from NewlineNode.java:104:in `interpret'
    from BlockNode.java:71:in `interpret'
    from InterpretedMethod.java:180:in `call'
    from DefaultMethod.java:174:in `call'
    from CachingCallSite.java:309:in `cacheAndCall'
    from CachingCallSite.java:148:in `call'
    from FCallOneArgNode.java:36:in `interpret'
    from NewlineNode.java:104:in `interpret'
    from RescueNode.java:199:in `executeBody'
    from RescueNode.java:118:in `interpretWithJavaExceptions'
    from RescueNode.java:110:in `interpret'
    from InterpretedMethod.java:180:in `call'
    from DefaultMethod.java:174:in `call'
    from CachingCallSite.java:309:in `cacheAndCall'
    from CachingCallSite.java:148:in `call'
    from CallOneArgNode.java:57:in `interpret'
    from NewlineNode.java:104:in `interpret'
    from BlockNode.java:71:in `interpret'
    from InterpretedMethod.java:180:in `call'
    from DefaultMethod.java:174:in `call'
    from CachingCallSite.java:309:in `cacheAndCall'
    from CachingCallSite.java:148:in `call'
    from gem:24:in `rescue_1$RUBY$__rescue___0'
    from gem:23:in `__file__'
    from gem:-1:in `load'
    from Ruby.java:692:in `runScript'
    from Ruby.java:575:in `runNormally'
    from Ruby.java:418:in `runFromMain'
    from Main.java:286:in `run'
    from Main.java:128:in `run'
    from Main.java:97:in `main'

これはエラー メッセージでも成功メッセージでもありません。