Java 9 Class Count

nebhale · nebhale · commit 82aae9477dd8 · 2018-02-12T15:25:13.000-08:00
Previously, when attempting to count the classes that could be loaded from the JRE, Java 9 JVMs were underrepresented due to the new module packaging format. The format is not examinable using tools shipped in the JRE (jimage from the JDK would be able to do it) so this change places a constant in for the number of classes contributed by the Java 9 JRE. [resolves cloudfoundry#543]
diff --git a/lib/java_buildpack/jre/open_jdk_like_memory_calculator.rb b/lib/java_buildpack/jre/open_jdk_like_memory_calculator.rb
@@ -76,7 +76,8 @@ def actual_class_count(root)
         (root + '**/*.class').glob.count +
           (root + '**/*.groovy').glob.count +
           (root + '**/*.jar').glob(File::FNM_DOTMATCH).reject(&:directory?)
-                             .inject(0) { |a, e| a + archive_class_count(e) }
+                             .inject(0) { |a, e| a + archive_class_count(e) } +
+          (@droplet.java_home.java_9_or_later? ? 42_215 : 0)
       end
 
       def archive_class_count(archive)
diff --git a/spec/java_buildpack/jre/open_jdk_like_memory_calculator_spec.rb b/spec/java_buildpack/jre/open_jdk_like_memory_calculator_spec.rb
@@ -27,9 +27,15 @@
 
   let(:configuration) { { 'stack_threads' => '200' } }
 
-  let(:java_home) { JavaBuildpack::Component::MutableJavaHome.new }
+  let(:java_home) do
+    java_home = JavaBuildpack::Component::MutableJavaHome.new
+    java_home.version = version_8
+    return java_home
+  end
 
-  let(:version_8) { VERSION_8 = JavaBuildpack::Util::TokenizedVersion.new('1.8.0_+') }
+  let(:version_8) { JavaBuildpack::Util::TokenizedVersion.new('1.8.0_162') }
+
+  let(:version_9) { JavaBuildpack::Util::TokenizedVersion.new('9.0.4_11') }
 
   it 'copies executable to bin directory',
      cache_fixture: 'stub-memory-calculator.tar.gz' do
@@ -105,4 +111,21 @@
     expect(environment_variables).to include('MALLOC_ARENA_MAX=2')
   end
 
+  context 'when java 9' do
+
+    it 'creates memory calculation command',
+       app_fixture: 'jre_memory_calculator_application' do
+
+      java_home.version = version_9
+
+      command = component.memory_calculation_command
+
+      expect(command).to eq('CALCULATED_MEMORY=$($PWD/.java-buildpack/open_jdk_like_memory_calculator/bin/' \
+                            'java-buildpack-memory-calculator-0.0.0 -totMemory=$MEMORY_LIMIT -stackThreads=200 ' \
+                            '-loadedClasses=14777 -poolType=metaspace -vmOptions="$JAVA_OPTS") && echo JVM Memory ' \
+                            'Configuration: $CALCULATED_MEMORY && JAVA_OPTS="$JAVA_OPTS $CALCULATED_MEMORY"')
+    end
+
+  end
+
 end
