我正试图使用开放式nlp Ruby gem通过RJB(Ruby Java Bridge)访问Java OpenNLP处理器。我不是Java程序员,所以我不知道如何解决这个问题。任何关于解决、调试、收集更多信息等方面的建议都将不胜感激。
环境为Windows 8、Ruby 1.9.3p448、Rails 4.0.0、JDK 1.7.0-40 x586。宝石是rjb 1.4.8和louismullie/open nlp 0.1.4。为了记录在案,这个文件在JRuby中运行,但我在那个环境中遇到了其他问题,现在我更喜欢保留原生Ruby。
简而言之,打开的nlp-gem失败了,缺少java.lang.NullPointerException和Ruby错误方法。我不知道为什么会发生这种情况,但在我看来,Jars文件的动态加载opennlp.tools.postag.POSTaggerME@1b5080a无法访问,可能是因为OpenNLP::Bindings::Utils.tagWithArrayList的设置不正确。OpenNLP::Bindings是Ruby。Utils及其方法是Java。Utils被认为是“默认”的Jars和Class文件,这可能很重要。
我做错了什么,在这里?谢谢
我正在运行的代码是直接从中复制的
github/open-nlp
。我的代码副本是:
class OpennlpTryer
$DEBUG=false
# From https://github.com/louismullie/open-nlp
# Hints: Dir.pwd; File.expand_path('../../Gemfile', __FILE__);
# Load the module
require 'open-nlp'
#require 'jruby-jars'
=begin
# Alias "write" to "print" to monkeypatch the NoMethod write error
java_import java.io.PrintStream
class PrintStream
java_alias(:write, :print, [java.lang.String])
end
=end
=begin
# Display path of jruby-jars jars...
puts JRubyJars.core_jar_path # => path to jruby-core-VERSION.jar
puts JRubyJars.stdlib_jar_path # => path to jruby-stdlib-VERSION.jar
=end
puts ENV['CLASSPATH']
# Set an alternative path to look for the JAR files.
# Default is gem's bin folder.
# OpenNLP.jar_path = '/path_to_jars/'
OpenNLP.jar_path = File.join(ENV["GEM_HOME"],"gems/open-nlp-0.1.4/bin/")
puts OpenNLP.jar_path
# Set an alternative path to look for the model files.
# Default is gem's bin folder.
# OpenNLP.model_path = '/path_to_models/'
OpenNLP.model_path = File.join(ENV["GEM_HOME"],"gems/open-nlp-0.1.4/bin/")
puts OpenNLP.model_path
# Pass some alternative arguments to the Java VM.
# Default is ['-Xms512M', '-Xmx1024M'].
# OpenNLP.jvm_args = ['-option1', '-option2']
OpenNLP.jvm_args = ['-Xms512M', '-Xmx1024M']
# Redirect VM output to log.txt
OpenNLP.log_file = 'log.txt'
# Set default models for a language.
# OpenNLP.use :language
OpenNLP.use :english # Make sure this is lower case!!!!
# Simple tokenizer
OpenNLP.load
sent = "The death of the poet was kept from his poems."
tokenizer = OpenNLP::SimpleTokenizer.new
tokens = tokenizer.tokenize(sent).to_a
# => %w[The death of the poet was kept from his poems .]
puts "Tokenize #{tokens}"
# Maximum entropy tokenizer, chunker and POS tagger
OpenNLP.load
chunker = OpenNLP::ChunkerME.new
tokenizer = OpenNLP::TokenizerME.new
tagger = OpenNLP::POSTaggerME.new
sent = "The death of the poet was kept from his poems."
tokens = tokenizer.tokenize(sent).to_a
# => %w[The death of the poet was kept from his poems .]
puts "Tokenize #{tokens}"
tags = tagger.tag(tokens).to_a
# => %w[DT NN IN DT NN VBD VBN IN PRP$ NNS .]
puts "Tags #{tags}"
chunks = chunker.chunk(tokens, tags).to_a
# => %w[B-NP I-NP B-PP B-NP I-NP B-VP I-VP B-PP B-NP I-NP O]
puts "Chunks #{chunks}"
# Abstract Bottom-Up Parser
OpenNLP.load
sent = "The death of the poet was kept from his poems."
parser = OpenNLP::Parser.new
parse = parser.parse(sent)
=begin
parse.get_text.should eql sent
parse.get_span.get_start.should eql 0
parse.get_span.get_end.should eql 46
parse.get_child_count.should eql 1
=end
child = parse.get_children[0]
child.text # => "The death of the poet was kept from his poems."
child.get_child_count # => 3
child.get_head_index #=> 5
child.get_type # => "S"
puts "Child: #{child}"
# Maximum Entropy Name Finder*
OpenNLP.load
# puts File.expand_path('.', __FILE__)
text = File.read('./spec/sample.txt').gsub!("\n", "")
tokenizer = OpenNLP::TokenizerME.new
segmenter = OpenNLP::SentenceDetectorME.new
puts "Tokenizer: #{tokenizer}"
puts "Segmenter: #{segmenter}"
ner_models = ['person', 'time', 'money']
ner_finders = ner_models.map do |model|
OpenNLP::NameFinderME.new("en-ner-#{model}.bin")
end
puts "NER Finders: #{ner_finders}"
sentences = segmenter.sent_detect(text)
puts "Sentences: #{sentences}"
named_entities = []
sentences.each do |sentence|
tokens = tokenizer.tokenize(sentence)
ner_models.each_with_index do |model, i|
finder = ner_finders[i]
name_spans = finder.find(tokens)
name_spans.each do |name_span|
start = name_span.get_start
stop = name_span.get_end-1
slice = tokens[start..stop].to_a
named_entities << [slice, model]
end
end
end
puts "Named Entities: #{named_entities}"
# Loading specific models
# Just pass the name of the model file to the constructor. The gem will search for the file in the OpenNLP.model_path folder.
OpenNLP.load
tokenizer = OpenNLP::TokenizerME.new('en-token.bin')
tagger = OpenNLP::POSTaggerME.new('en-pos-perceptron.bin')
name_finder = OpenNLP::NameFinderME.new('en-ner-person.bin')
# etc.
puts "Tokenizer: #{tokenizer}"
puts "Tagger: #{tagger}"
puts "Name Finder: #{name_finder}"
# Loading specific classes
# You may want to load specific classes from the OpenNLP library that are not loaded by default. The gem provides an API to do this:
# Default base class is opennlp.tools.
OpenNLP.load_class('SomeClassName')
# => OpenNLP::SomeClassName
# Here, we specify another base class.
OpenNLP.load_class('SomeOtherClass', 'opennlp.tools.namefind')
# => OpenNLP::SomeOtherClass
end
失败的一行是第73行:(标记==正在处理的句子。)
tags = tagger.tag(tokens).to_a #
# => %w[DT NN IN DT NN VBD VBN IN PRP$ NNS .]
tagger.tag调用打开的nlp/classes.rb第13行,也就是抛出错误的地方。那里的代码是:
class OpenNLP::POSTaggerME < OpenNLP::Base
unless RUBY_PLATFORM =~ /java/
def tag(*args)
OpenNLP::Bindings::Utils.tagWithArrayList(@proxy_inst, args[0]) # <== Line 13
end
end
end
此时抛出的Ruby错误是:“method_missing”:未知异常(NullPointerException)。调试时,我发现错误java.lang.NullPointerException.args[0]是正在处理的句子@代理指令是opennlp.tools.postag.POSTaggerME@1b5080a.
OpenNLP::Bindings设置Java环境。例如,它设置要加载的Jars和这些Jars中的类。在第54行中,它为RJB设置了默认值,RJB应按如下方式设置OpenNLP::Bindings::Utils及其方法:
# Add in Rjb workarounds.
unless RUBY_PLATFORM =~ /java/
self.default_jars << 'utils.jar'
self.default_classes << ['Utils', '']
end
utils.jar和utils.java在CLASSPATH中,其他jar正在加载。它们正在被访问,这是经过验证的,因为如果其他Jar不存在,它们就会抛出错误消息。CLASSPATH是:
.;C:\Program Files (x86)Java\jdk1.7.0_40\lib;C:\Program Files (x86)Java\jre7\lib;D:\BitNami\rubystack-1.9.3-12\ruby\lib\ruby\gems\1.9.1\gems\open-nlp-0.1.4\bin
应用程序Jars位于D:\BitNami\rubystack-1.9.3-12\rubb\lib\rubb\gems\1.9.1\gems\open-nlp-0.1.4\bin中,同样,如果它们不在那里,我会在其他Jars上收到错误消息。中的Jars和Java文件。。。\垃圾箱包括:
jwnl-1.3.3.jar
opennlp-maxent-3.0.2-incubating.jar
opennlp-tools-1.5.2-incubating.jar
opennlp-uima-1.5.2-incubating.jar
utils.jar
Utils.java
Utils.java如下所示:
import java.util.Arrays;
import java.util.ArrayList;
import java.lang.String;
import opennlp.tools.postag.POSTagger;
import opennlp.tools.chunker.ChunkerME;
import opennlp.tools.namefind.NameFinderME; // interface instead?
import opennlp.tools.util.Span;
// javac -cp '.:opennlp.tools.jar' Utils.java
// jar cf utils.jar Utils.class
public class Utils {
public static String[] tagWithArrayList(POSTagger posTagger, ArrayList[] objectArray) {
return posTagger.tag(getStringArray(objectArray));
}
public static Object[] findWithArrayList(NameFinderME nameFinder, ArrayList[] tokens) {
return nameFinder.find(getStringArray(tokens));
}
public static Object[] chunkWithArrays(ChunkerME chunker, ArrayList[] tokens, ArrayList[] tags) {
return chunker.chunk(getStringArray(tokens), getStringArray(tags));
}
public static String[] getStringArray(ArrayList[] objectArray) {
String[] stringArray = Arrays.copyOf(objectArray, objectArray.length, String[].class);
return stringArray;
}
}
因此,它应该定义tagWithArrayList并导入opennlp.tools.postagg.POSTagger
正如预期的那样,工具Jar文件opennlp-tools-1.5.2-cubating.Jar包括postag/POSTagger和POSTaggerME类文件。
错误消息为:
D:\BitNami\rubystack-1.9.3-12\ruby\bin\ruby.exe -e $stdout.sync=true;$stderr.sync=true;load($0=ARGV.shift) D:/BitNami/rubystack-1.9.3-12/projects/RjbTest/app/helpers/opennlp_tryer.rb
.;C:\Program Files (x86)\Java\jdk1.7.0_40\lib;C:\Program Files (x86)\Java\jre7\lib;D:\BitNami\rubystack-1.9.3-12\ruby\lib\ruby\gems\1.9.1\gems\open-nlp-0.1.4\bin
D:/BitNami/rubystack-1.9.3-12/ruby/lib/ruby/gems/1.9.1/gems/open-nlp-0.1.4/bin/
D:/BitNami/rubystack-1.9.3-12/ruby/lib/ruby/gems/1.9.1/gems/open-nlp-0.1.4/bin/
Tokenize ["The", "death", "of", "the", "poet", "was", "kept", "from", "his", "poems", "."]
Tokenize ["The", "death", "of", "the", "poet", "was", "kept", "from", "his", "poems", "."]
D:/BitNami/rubystack-1.9.3-12/ruby/lib/ruby/gems/1.9.1/gems/open-nlp-0.1.4/lib/open-nlp/classes.rb:13:in `method_missing': unknown exception (NullPointerException)
from D:/BitNami/rubystack-1.9.3-12/ruby/lib/ruby/gems/1.9.1/gems/open-nlp-0.1.4/lib/open-nlp/classes.rb:13:in `tag'
from D:/BitNami/rubystack-1.9.3-12/projects/RjbTest/app/helpers/opennlp_tryer.rb:73:in `<class:OpennlpTryer>'
from D:/BitNami/rubystack-1.9.3-12/projects/RjbTest/app/helpers/opennlp_tryer.rb:1:in `<top (required)>'
from -e:1:in `load'
from -e:1:in `<main>'
修改后的Utils.java:
import java.util.Arrays;
import java.util.Object;
import java.lang.String;
import opennlp.tools.postag.POSTagger;
import opennlp.tools.chunker.ChunkerME;
import opennlp.tools.namefind.NameFinderME; // interface instead?
import opennlp.tools.util.Span;
// javac -cp '.:opennlp.tools.jar' Utils.java
// jar cf utils.jar Utils.class
public class Utils {
public static String[] tagWithArrayList(POSTagger posTagger, Object[] objectArray) {
return posTagger.tag(getStringArray(objectArray));
}f
public static Object[] findWithArrayList(NameFinderME nameFinder, Object[] tokens) {
return nameFinder.find(getStringArray(tokens));
}
public static Object[] chunkWithArrays(ChunkerME chunker, Object[] tokens, Object[] tags) {
return chunker.chunk(getStringArray(tokens), getStringArray(tags));
}
public static String[] getStringArray(Object[] objectArray) {
String[] stringArray = Arrays.copyOf(objectArray, objectArray.length, String[].class);
return stringArray;
}
}
修改的错误消息:
Uncaught exception: uninitialized constant OpennlpTryer::ArrayStoreException
D:/BitNami/rubystack-1.9.3-12/projects/RjbTest/app/helpers/opennlp_tryer.rb:81:in `rescue in <class:OpennlpTryer>'
D:/BitNami/rubystack-1.9.3-12/projects/RjbTest/app/helpers/opennlp_tryer.rb:77:in `<class:OpennlpTryer>'
D:/BitNami/rubystack-1.9.3-12/projects/RjbTest/app/helpers/opennlp_tryer.rb:1:in `<top (required)>'
Utils.java修改为“import java.lang.Object;”时出现的修改错误:
未捕获的异常:未初始化的常量OpennlpTryer::ArrayStoreException
D: /BitNami/rubystack-1.9.3-12/projects/RjbTest/app/helpers/opennlp_tryer.rb:81:in`rescue in<类:OpennlpTryer>'
D: /BitNami/rubystack-1.9.3-12/projects/RjbTest/app/helpers/opennlp_tryer.rb:77:in`<类:OpennlpTryer>'
D: /BitNami/rubystack-1.9.3-12/projects/RjbTest/app/helpers/opennlp_tryer.rb:1:in`<顶部(必需)>'
从OpennlpTryer中删除的救援显示类中存在错误。rb:
Uncaught exception: uninitialized constant OpenNLP::POSTaggerME::ArrayStoreException
D:/BitNami/rubystack-1.9.3-12/ruby/lib/ruby/gems/1.9.1/gems/open-nlp-0.1.4/lib/open-nlp/classes.rb:16:in `rescue in tag'
D:/BitNami/rubystack-1.9.3-12/ruby/lib/ruby/gems/1.9.1/gems/open-nlp-0.1.4/lib/open-nlp/classes.rb:13:in `tag'
D:/BitNami/rubystack-1.9.3-12/projects/RjbTest/app/helpers/opennlp_tryer.rb:78:in `<class:OpennlpTryer>'
D:/BitNami/rubystack-1.9.3-12/projects/RjbTest/app/helpers/opennlp_tryer.rb:1:in `<top (required)>'
同样的错误,但删除了所有救援,所以它是“原生Ruby”
Uncaught exception: unknown exception
D:/BitNami/rubystack-1.9.3-12/ruby/lib/ruby/gems/1.9.1/gems/open-nlp-0.1.4/lib/open-nlp/classes.rb:15:in `method_missing'
D:/BitNami/rubystack-1.9.3-12/ruby/lib/ruby/gems/1.9.1/gems/open-nlp-0.1.4/lib/open-nlp/classes.rb:15:in `tag'
D:/BitNami/rubystack-1.9.3-12/projects/RjbTest/app/helpers/opennlp_tryer.rb:78:in `<class:OpennlpTryer>'
D:/BitNami/rubystack-1.9.3-12/projects/RjbTest/app/helpers/opennlp_tryer.rb:1:in `<top (required)>'
修订后的Utils.java:
import java.util.Arrays;
import java.util.ArrayList;
import java.lang.String;
import opennlp.tools.postag.POSTagger;
import opennlp.tools.chunker.ChunkerME;
import opennlp.tools.namefind.NameFinderME; // interface instead?
import opennlp.tools.util.Span;
// javac -cp '.:opennlp.tools.jar' Utils.java
// jar cf utils.jar Utils.class
public class Utils {
public static String[] tagWithArrayList(
System.out.println("Tokens: ("+objectArray.getClass().getSimpleName()+"): \n"+objectArray);
POSTagger posTagger, ArrayList[] objectArray) {
return posTagger.tag(getStringArray(objectArray));
}
public static Object[] findWithArrayList(NameFinderME nameFinder, ArrayList[] tokens) {
return nameFinder.find(getStringArray(tokens));
}
public static Object[] chunkWithArrays(ChunkerME chunker, ArrayList[] tokens, ArrayList[] tags) {
return chunker.chunk(getStringArray(tokens), getStringArray(tags));
}
public static String[] getStringArray(ArrayList[] objectArray) {
String[] stringArray = Arrays.copyOf(objectArray, objectArray.length, String[].class);
return stringArray;
}
}
我在Utils.class上运行了cavaj,我从util.jar中解压了它,这就是我发现的。它与Utils.java有很大的不同。两者都安装了开放的nlp 1.4.8 gem。我不知道这是否是问题的根本原因,但这个文件是它崩溃的核心,我们有很大的差异。我们应该使用哪一个?
import java.util.ArrayList;
import java.util.Arrays;
import opennlp.tools.chunker.ChunkerME;
import opennlp.tools.namefind.NameFinderME;
import opennlp.tools.postag.POSTagger;
public class Utils
{
public Utils()
{
}
public static String[] tagWithArrayList(POSTagger postagger, ArrayList aarraylist[])
{
return postagger.tag(getStringArray(aarraylist));
}
public static Object[] findWithArrayList(NameFinderME namefinderme, ArrayList aarraylist[])
{
return namefinderme.find(getStringArray(aarraylist));
}
public static Object[] chunkWithArrays(ChunkerME chunkerme, ArrayList aarraylist[], ArrayList aarraylist1[])
{
return chunkerme.chunk(getStringArray(aarraylist), getStringArray(aarraylist1));
}
public static String[] getStringArray(ArrayList aarraylist[])
{
String as[] = (String[])Arrays.copyOf(aarraylist, aarraylist.length, [Ljava/lang/String;);
return as;
}
}
自2007年10月起使用的Utils.java,已编译并压缩为Utils.jar:
导入java.util.Arrays;
导入java.util.ArrayList;
导入java.lang.String;
导入opennlp.tools.postagg.POSTagger;
导入opennlp.tools.chunker.ChunkerME;
导入opennlp.tools.namefind.NameFinderME;//接口?
导入opennlp.tools.util.Span;
//javac-cp'。:opennlp.tools.jar的Utils.java
//jar cf实用工具.jar实用工具类
公共类Utils{
public static String[]tagWithArrayList(POSTagger POSTagger,ArrayList[]objectArray){
return posTagger.tag(getStringArray(objectArray));
}
公共静态对象[]findWithArrayList(NameFinderME nameFinder,ArrayList[]令牌){
return nameFinder.find(getStringArray(tokens));
}
public static Object[]chunkWithArrays(ChunkerME chunker、ArrayList[]令牌、ArrayList[]标记){
return chunker.chunk(getStringArray(tokens),getStringArray(tags));
}
public static String[]getStringArray(ArrayList[]objectArray){
String[]stringArray=Arrays.copyOf(objectArray,objectArray.length,String[].class);
return字符串数组;
}
}
故障发生在第110行的BindIt::Binding::load_klass中,此处为:
# Private function to load classes.
# Doesn't check if initialized.
def load_klass(klass, base, name=nil)
base += '.' unless base == ''
fqcn = "#{base}#{klass}"
name ||= klass
if RUBY_PLATFORM =~ /java/
rb_class = java_import(fqcn)
if name != klass
if rb_class.is_a?(Array)
rb_class = rb_class.first
end
const_set(name.intern, rb_class)
end
else
rb_class = Rjb::import(fqcn) # <== This is line 110
const_set(name.intern, rb_class)
end
end
消息如下,但就所标识的特定方法而言,它们是不一致的。每次运行都可以显示不同的方法,POSTagger、ChunkerME或NameFinderME中的任何一个。
D:/BitNami/rubystack-1.9.3-12/ruby/lib/ruby/gems/1.9.1/gems/bind-it-0.2.7/lib/bind-it/binding.rb:110:in `import': opennlp/tools/namefind/NameFinderME (NoClassDefFoundError)
from D:/BitNami/rubystack-1.9.3-12/ruby/lib/ruby/gems/1.9.1/gems/bind-it-0.2.7/lib/bind-it/binding.rb:110:in `load_klass'
from D:/BitNami/rubystack-1.9.3-12/ruby/lib/ruby/gems/1.9.1/gems/bind-it-0.2.7/lib/bind-it/binding.rb:89:in `block in load_default_classes'
from D:/BitNami/rubystack-1.9.3-12/ruby/lib/ruby/gems/1.9.1/gems/bind-it-0.2.7/lib/bind-it/binding.rb:87:in `each'
from D:/BitNami/rubystack-1.9.3-12/ruby/lib/ruby/gems/1.9.1/gems/bind-it-0.2.7/lib/bind-it/binding.rb:87:in `load_default_classes'
from D:/BitNami/rubystack-1.9.3-12/ruby/lib/ruby/gems/1.9.1/gems/bind-it-0.2.7/lib/bind-it/binding.rb:56:in `bind'
from D:/BitNami/rubystack-1.9.3-12/ruby/lib/ruby/gems/1.9.1/gems/open-nlp-0.1.4/lib/open-nlp.rb:14:in `load'
from D:/BitNami/rubystack-1.9.3-12/projects/RjbTest/app/helpers/opennlp_tryer.rb:54:in `<class:OpennlpTryer>'
from D:/BitNami/rubystack-1.9.3-12/projects/RjbTest/app/helpers/opennlp_tryer.rb:1:in `<top (required)>'
from -e:1:in `load'
from -e:1:in `<main>'
关于这些错误的有趣之处在于,它们源自OpennlpTryer行54,即:
OpenNLP.load
此时,OpenNLP启动RJB,RJB使用BindIt加载jar和类。这远远早于我在这个问题开始时看到的错误。然而,我忍不住认为这一切都是相关的。我真的一点也不理解这些错误的前后矛盾。
我可以将日志记录函数添加到Utils.java中,在添加“import java.io.*”后对其进行编译并压缩。然而,由于这些错误,我将其删除,因为我不知道是否涉及它。我不认为是这样。然而,由于这些错误是在加载过程中发生的,因此无论如何都不会调用该方法,因此在那里进行日志记录不会有帮助。。。
对于其他每个jar,加载jar,然后使用RJB导入每个类。Utils的处理方式不同,并被指定为“默认”。据我所知,执行Utils.class是为了加载自己的类吗?
2007年10月更新:
我想我就在这里。首先,我在替换Utils.java时遇到了一些问题,正如我今天早些时候所描述的那样。在我安装修复程序之前,这个问题可能需要解决。
其次,我现在理解了POSTagger和POSTaggerME之间的区别,因为ME的意思是最大熵。测试代码试图调用POSTaggerME,但在我看来,Utils.java在实现时支持POSTagger。我尝试更改测试代码以调用POSTagger,但它说找不到初始值设定项。看看每一个的来源,我猜在这里,我认为POSTagger的存在只是为了支持实现它的POSTaggerME。
来源是
opennlp-tools
文件opennlp-tools-1.5.2-cubating-sources.jar。
我不明白乌蒂尔的全部原因是什么?为什么bindings.rb中提供的jars/classes还不够?这感觉像是一场糟糕的猴痘。我的意思是,看看bindings.rb首先做了什么:
# Default JARs to load.
self.default_jars = [
'jwnl-1.3.3.jar',
'opennlp-tools-1.5.2-incubating.jar',
'opennlp-maxent-3.0.2-incubating.jar',
'opennlp-uima-1.5.2-incubating.jar'
]
# Default namespace.
self.default_namespace = 'opennlp.tools'
# Default classes.
self.default_classes = [
# OpenNLP classes.
['AbstractBottomUpParser', 'opennlp.tools.parser'],
['DocumentCategorizerME', 'opennlp.tools.doccat'],
['ChunkerME', 'opennlp.tools.chunker'],
['DictionaryDetokenizer', 'opennlp.tools.tokenize'],
['NameFinderME', 'opennlp.tools.namefind'],
['Parser', 'opennlp.tools.parser.chunking'],
['Parse', 'opennlp.tools.parser'],
['ParserFactory', 'opennlp.tools.parser'],
['POSTaggerME', 'opennlp.tools.postag'],
['SentenceDetectorME', 'opennlp.tools.sentdetect'],
['SimpleTokenizer', 'opennlp.tools.tokenize'],
['Span', 'opennlp.tools.util'],
['TokenizerME', 'opennlp.tools.tokenize'],
# Generic Java classes.
['FileInputStream', 'java.io'],
['String', 'java.lang'],
['ArrayList', 'java.util']
]
# Add in Rjb workarounds.
unless RUBY_PLATFORM =~ /java/
self.default_jars << 'utils.jar'
self.default_classes << ['Utils', '']
end