Import JRuby extension

.github/workflows/test.yml

@@ -41,3 +41,17 @@ jobs:
     - name: Run test
       run: bundle exec rake compile test
       timeout-minutes: 5
+
+  build-jruby:
+    name: build jruby
+    runs-on: ubuntu-latest
+    steps:
+    - uses: actions/checkout@v4
+    - name: Set up Ruby
+      uses: ruby/setup-ruby@v1
+      with:
+        ruby-version: jruby-10
+        bundler-cache: true # 'bundle install' and cache
+    - name: Run test
+      run: bundle exec rake compile test
+      timeout-minutes: 5

.gitignore

@@ -10,3 +10,4 @@
 *.bundle
 *.so
 *.dll
+/ext/java/lib/zlib.jar

Gemfile

@@ -7,3 +7,4 @@ gem "test-unit"
 gem "test-unit-ruby-core"
 gem "rake"
 gem "rake-compiler"
+gem "ruby-maven", platform: :jruby

Mavenfile

@@ -0,0 +1,7 @@
+#-*- mode: ruby -*-
+
+jar 'org.jruby:jzlib:1.1.5'
+
+plugin :dependency, '2.8', :outputFile => 'pkg/classpath'
+
+# vim: syntax=Ruby

Rakefile

@@ -12,11 +12,31 @@ end
 
 Rake::TestTask.new(:test_internal) do |t|
   t.libs << "test/lib"
+  t.libs << "ext/java/lib" if RUBY_ENGINE == "jruby"
   t.ruby_opts << "-rhelper"
   t.test_files = FileList["test/**/test_*.rb"]
 end
 
-require 'rake/extensiontask'
-Rake::ExtensionTask.new("zlib")
+if RUBY_PLATFORM =~ /java/
+  require 'rake/javaextensiontask'
+  Rake::JavaExtensionTask.new("zlib") do |ext|
+    require 'maven/ruby/maven'
+    # force load of versions to overwrite constants with values from repo.
+    load './ext/java/lib/zlib/versions.rb'
+    # uses Mavenfile to write classpath into pkg/classpath
+    # and tell maven via system properties the snakeyaml version
+    # this is basically the same as running from the commandline:
+    # rmvn dependency:build-classpath -Dsnakeyaml.version='use version from Psych::DEFAULT_SNAKEYAML_VERSION here'
+    Maven::Ruby::Maven.new.exec('dependency:build-classpath', '-Dverbose=true')
+    ext.source_version = '21'
+    ext.target_version = '21'
+    ext.classpath = File.read('pkg/classpath')
+    ext.ext_dir = 'ext/java'
+    ext.lib_dir = 'ext/java/lib'
+  end
+else
+  require 'rake/extensiontask'
+  Rake::ExtensionTask.new("zlib")
+end
 
 task :default => [:compile, :test]

ext/java/lib/zlib.rb

@@ -0,0 +1,33 @@
+# frozen_string_literal: true
+
+require 'zlib.jar'
+require 'zlib/versions'
+
+require 'jar-dependencies'
+require_jar('org.jruby', 'jzlib', Zlib::JZLIB_VERSION)
+
+JRuby::Util.load_ext('org.jruby.ext.zlib.ZlibLibrary')
+
+module Zlib
+  autoload :StringIO, 'stringio'
+
+  def self.gzip(src, opts = nil)
+    if Hash === opts
+      level = opts[:level]
+      strategy = opts[:strategy]
+    end
+    io = StringIO.new("".b)
+    GzipWriter.new(io, level, strategy) do |writer|
+      writer.write(src)
+    end
+    io.string
+  end
+
+  def self.gunzip(src)
+    io = StringIO.new(src)
+    reader = GzipReader.new(io)
+    result = reader.read
+    reader.close
+    result
+  end
+end

ext/java/lib/zlib/versions.rb

@@ -0,0 +1,5 @@
+# frozen_string_literal: true
+
+module Zlib
+  JZLIB_VERSION = "1.1.5"
+end