Support --release option to build JRuby extension for older platforms (#201)

2 files changed, 38 insertions, 2 deletions

diff --git a/lib/rake/javaextensiontask.rb b/lib/rake/javaextensiontask.rb
index baf9c6c..5603afc 100644
--- a/lib/rake/javaextensiontask.rb
+++ b/lib/rake/javaextensiontask.rb
@@ -17,6 +17,9 @@ module Rake
     # Generate class files for specific VM version
     attr_accessor :target_version
 
+    # Compile for oldeer platform version
+    attr_accessor :release
+
     attr_accessor :encoding
 
     # Specify lint option
@@ -37,6 +40,7 @@ module Rake
       @debug          = false
       @source_version = '1.7'
       @target_version = '1.7'
+      @release        = nil
       @encoding       = nil
       @java_compiling = nil
       @lint_option    = nil
@@ -106,8 +110,7 @@ execute the Rake compilation task using the JRuby interpreter.
 
         javac_command_line = [
           "javac",
-          "-target", @target_version,
-          "-source", @source_version,
+          *java_target_args,
           java_lint_arg,
           "-d", tmp_path,
         ]
@@ -208,6 +211,14 @@ execute the Rake compilation task using the JRuby interpreter.
       end
     end
 
+    def java_target_args
+      if @release
+        ["--release=#{@release}"]
+      else
+        ["-target", @target_version, "-source", @source_version]
+      end
+    end
+
     #
     # Discover Java Extension Directories and build an extdirs arguments
     #
diff --git a/spec/lib/rake/javaextensiontask_spec.rb b/spec/lib/rake/javaextensiontask_spec.rb
index 7d8999a..1072b88 100644
--- a/spec/lib/rake/javaextensiontask_spec.rb
+++ b/spec/lib/rake/javaextensiontask_spec.rb
@@ -175,11 +175,13 @@ describe Rake::JavaExtensionTask do
       let(:extension) do
         Rake::JavaExtensionTask.new('extension_two') do |ext|
           ext.lint_option = lint_option if lint_option
+          ext.release = release if release
         end
       end
 
       context 'without a specified lint option' do
         let(:lint_option) { nil }
+        let(:release) { nil }
 
         it 'should honor the lint option' do
           (extension.lint_option).should be_falsey
@@ -189,12 +191,35 @@ describe Rake::JavaExtensionTask do
 
       context "with a specified lint option of 'deprecated'" do
         let(:lint_option) { 'deprecated'.freeze }
+        let(:release) { nil }
 
         it 'should honor the lint option' do
           (extension.lint_option).should eq lint_option
           (extension.send :java_lint_arg).should eq '-Xlint:deprecated'
         end
       end
+
+      context "without release option" do
+        let(:lint_option) { nil }
+        let(:release) { nil }
+
+        it 'should generate -target and -source build options' do
+          extension.target_version = "1.8"
+          extension.source_version = "1.8"
+          (extension.send :java_target_args).should eq ["-target", "1.8", "-source", "1.8"]
+        end
+      end
+
+      context "with release option" do
+        let(:lint_option) { nil }
+        let(:release) { '8' }
+
+        it 'should generate --release option even with target_version/source_version' do
+          extension.target_version = "1.8"
+          extension.source_version = "1.8"
+          (extension.send :java_target_args).should eq ["--release=8"]
+        end
+      end
     end
   end
   private