51 files changed, 88 insertions, 22 deletions
diff --git a/all/build.gradle b/all/build.gradle
index 86f96814..ebd03277 100644
--- a/all/build.gradle
+++ b/all/build.gradle
@@ -1,6 +1,6 @@
 apply plugin: 'com.github.kt3k.coveralls'
 
-description = "Instrumentation: All"
+description = "OpenCensus All"
 
 buildscript {
     repositories {
@@ -16,8 +16,10 @@ buildscript {
 def subprojects = [
         project(':opencensus-api'),
         project(':core'),
+        project(':opencensus-impl-core'),
         project(':core_impl'),
         project(':core_impl_java'),
+        project(':opencensus-impl'),
 ]
 
 for (subproject in rootProject.subprojects) {
@@ -43,6 +45,7 @@ javadoc {
         options.links subproject.javadoc.options.links.toArray(new String[0])
     }
     exclude 'io/opencensus/internal/**'
+    exclude 'io/opencensus/trace/internal/**'
 }
 
 task jacocoMerge(type: JacocoMerge) {
diff --git a/api/src/main/java/io/opencensus/common/Internal.java b/api/src/main/java/io/opencensus/common/Internal.java
index 9d540e21..fee892c3 100644
--- a/api/src/main/java/io/opencensus/common/Internal.java
+++ b/api/src/main/java/io/opencensus/common/Internal.java
@@ -20,8 +20,8 @@ import java.lang.annotation.RetentionPolicy;
 import java.lang.annotation.Target;
 
 /**
- * Annotates a program element (class, method, package etc) which is internal to opencensus, not
- * part of the public API, and should not be used by users of the opencensus library.
+ * Annotates a program element (class, method, package etc) which is internal to OpenCensus, not
+ * part of the public API, and should not be used by users of the OpenCensus library.
  */
 @Internal
 @Retention(RetentionPolicy.SOURCE)
diff --git a/benchmarks/build.gradle b/benchmarks/build.gradle
index 5203885a..62fda00c 100644
--- a/benchmarks/build.gradle
+++ b/benchmarks/build.gradle
@@ -23,9 +23,9 @@ jmh {
 }
 
 dependencies {
-    compile project(':core'),
-            project(':core_impl')
-            project(':core_impl_java')
+    compile project(':opencensus-api'),
+            project(':opencensus-impl-core')
+            project(':opencensus-impl')
 }
 
 compileJmhJava {
diff --git a/core/README.md b/core/README.md
index b4dfea18..2109a4bd 100644
--- a/core/README.md
+++ b/core/README.md
@@ -1,4 +1,4 @@
-Instrumentation API
+Will be ported to io.opencensus soon in api/.
 ======================================================
 
 * Java 6 and Android compatible.
diff --git a/core_impl/README.md b/core_impl/README.md
index 901177c8..4d4c64e7 100644
--- a/core_impl/README.md
+++ b/core_impl/README.md
@@ -1,4 +1,4 @@
-OpenCensus implementation
+Will be ported to io.opencensus soon in impl_core/.
 ======================================================
 
 * The main implementation shared between Java and Android.
diff --git a/core_impl/build.gradle b/core_impl/build.gradle
index 65a752a4..73593aa2 100644
--- a/core_impl/build.gradle
+++ b/core_impl/build.gradle
@@ -2,13 +2,17 @@ description = 'OpenCensus Core Impl'
 
 dependencies {
     compile project(':core'),
+            project(':opencensus-api'),
+            project(':opencensus-impl-core'),
             libraries.guava
 
-    compileOnly libraries.auto_value
-
     testCompile project(':core')
 
     signature "org.codehaus.mojo.signature:java16:+@signature"
 }
 
-javadoc.exclude 'io/opencensus/internal/**'
-\ No newline at end of file
+// Disable javadoc because fails with the error:
+// javadoc: error - No public or protected classes found to document.
+javadoc {
+    enabled = false
+}
+\ No newline at end of file
diff --git a/core_impl_android/README.md b/core_impl_android/README.md
index ad7bb9b1..f7ec5cdd 100644
--- a/core_impl_android/README.md
+++ b/core_impl_android/README.md
@@ -1,4 +1,4 @@
-OpenCensus Android implementation
+Will be ported to io.opencensus soon in impl_lite/.
 ======================================================
 
 * Android compatible.
diff --git a/core_impl_java/README.md b/core_impl_java/README.md
index 3dee26f9..0a33eee1 100644
--- a/core_impl_java/README.md
+++ b/core_impl_java/README.md
@@ -1,4 +1,4 @@
-OpenCensus Java implementation
+Will be ported to io.opencensus soon in impl/.
 ======================================================
 
 * Java 7 compatible.
diff --git a/core_impl_java/build.gradle b/core_impl_java/build.gradle
index da47efc5..4c17d2b5 100644
--- a/core_impl_java/build.gradle
+++ b/core_impl_java/build.gradle
@@ -10,9 +10,7 @@ apply plugin: 'java'
 dependencies {
     compile project(':core'),
             project(':core_impl'),
-            libraries.disruptor
+            project(':opencensus-impl')
 
     signature "org.codehaus.mojo.signature:java17:+@signature"
-}
-
-javadoc.exclude 'io/opencensus/internal/**'
-\ No newline at end of file
+}
+\ No newline at end of file
diff --git a/impl/README.md b/impl/README.md
new file mode 100644
index 00000000..3dee26f9
--- /dev/null
+++ b/impl/README.md
@@ -0,0 +1,5 @@
+OpenCensus Java implementation
+======================================================
+
+* Java 7 compatible.
+* Contains any classes not compatible with Android.
diff --git a/impl/build.gradle b/impl/build.gradle
new file mode 100644
index 00000000..be4e959c
--- /dev/null
+++ b/impl/build.gradle
@@ -0,0 +1,18 @@
+description = 'OpenCensus Implementation'
+
+apply plugin: 'java'
+
+[compileJava, compileTestJava].each() {
+    it.sourceCompatibility = 1.7
+    it.targetCompatibility = 1.7
+}
+
+dependencies {
+    compile project(':opencensus-api'),
+            project(':opencensus-impl-core'),
+            libraries.disruptor
+
+    signature "org.codehaus.mojo.signature:java17:+@signature"
+}
+
+javadoc.exclude 'io/opencensus/internal/**'
+\ No newline at end of file
diff --git a/core_impl_java/src/main/java/io/opencensus/internal/DisruptorEventQueue.java b/impl/src/main/java/io/opencensus/internal/DisruptorEventQueue.java
index 6360fe0e..6360fe0e 100644
--- a/core_impl_java/src/main/java/io/opencensus/internal/DisruptorEventQueue.java
+++ b/impl/src/main/java/io/opencensus/internal/DisruptorEventQueue.java
diff --git a/core_impl_java/src/main/java/io/opencensus/trace/TraceComponentImpl.java b/impl/src/main/java/io/opencensus/trace/TraceComponentImpl.java
index 5d0700bd..5d0700bd 100644
--- a/core_impl_java/src/main/java/io/opencensus/trace/TraceComponentImpl.java
+++ b/impl/src/main/java/io/opencensus/trace/TraceComponentImpl.java
diff --git a/core_impl_java/src/main/java/io/opencensus/trace/internal/ThreadLocalRandomHandler.java b/impl/src/main/java/io/opencensus/trace/internal/ThreadLocalRandomHandler.java
index 7cb9b2f2..7cb9b2f2 100644
--- a/core_impl_java/src/main/java/io/opencensus/trace/internal/ThreadLocalRandomHandler.java
+++ b/impl/src/main/java/io/opencensus/trace/internal/ThreadLocalRandomHandler.java
diff --git a/core_impl_java/src/test/java/io/opencensus/internal/DisruptorEventQueueTest.java b/impl/src/test/java/io/opencensus/internal/DisruptorEventQueueTest.java
index 83a00847..83a00847 100644
--- a/core_impl_java/src/test/java/io/opencensus/internal/DisruptorEventQueueTest.java
+++ b/impl/src/test/java/io/opencensus/internal/DisruptorEventQueueTest.java
diff --git a/core_impl_java/src/test/java/io/opencensus/trace/TracingTest.java b/impl/src/test/java/io/opencensus/trace/TracingTest.java
index 5f5fbeee..5f5fbeee 100644
--- a/core_impl_java/src/test/java/io/opencensus/trace/TracingTest.java
+++ b/impl/src/test/java/io/opencensus/trace/TracingTest.java
diff --git a/impl_core/README.md b/impl_core/README.md
new file mode 100644
index 00000000..901177c8
--- /dev/null
+++ b/impl_core/README.md
@@ -0,0 +1,5 @@
+OpenCensus implementation
+======================================================
+
+* The main implementation shared between Java and Android.
+* Java 7 and Android compatible.
diff --git a/impl_core/build.gradle b/impl_core/build.gradle
new file mode 100644
index 00000000..70de8aa6
--- /dev/null
+++ b/impl_core/build.gradle
@@ -0,0 +1,13 @@
+description = 'OpenCensus Core Implementation'
+
+dependencies {
+    compile project(':opencensus-api'),
+            libraries.guava
+
+    compileOnly libraries.auto_value
+
+    signature "org.codehaus.mojo.signature:java16:+@signature"
+}
+
+javadoc.exclude 'io/opencensus/internal/**'
+javadoc.exclude 'io/opencensus/trace/internal/**'
+\ No newline at end of file
diff --git a/core_impl/src/main/java/io/opencensus/common/MillisClock.java b/impl_core/src/main/java/io/opencensus/common/MillisClock.java
index fc1ac121..fc1ac121 100644
--- a/core_impl/src/main/java/io/opencensus/common/MillisClock.java
+++ b/impl_core/src/main/java/io/opencensus/common/MillisClock.java
diff --git a/core_impl/src/main/java/io/opencensus/internal/EventQueue.java b/impl_core/src/main/java/io/opencensus/internal/EventQueue.java
index d038e3d4..d038e3d4 100644
--- a/core_impl/src/main/java/io/opencensus/internal/EventQueue.java
+++ b/impl_core/src/main/java/io/opencensus/internal/EventQueue.java
diff --git a/core_impl/src/main/java/io/opencensus/internal/SimpleEventQueue.java b/impl_core/src/main/java/io/opencensus/internal/SimpleEventQueue.java
index 380e51d6..380e51d6 100644
--- a/core_impl/src/main/java/io/opencensus/internal/SimpleEventQueue.java
+++ b/impl_core/src/main/java/io/opencensus/internal/SimpleEventQueue.java
diff --git a/core_impl/src/main/java/io/opencensus/internal/TimestampConverter.java b/impl_core/src/main/java/io/opencensus/internal/TimestampConverter.java
index 1bf258c9..1bf258c9 100644
--- a/core_impl/src/main/java/io/opencensus/internal/TimestampConverter.java
+++ b/impl_core/src/main/java/io/opencensus/internal/TimestampConverter.java
diff --git a/core_impl/src/main/java/io/opencensus/internal/VarInt.java b/impl_core/src/main/java/io/opencensus/internal/VarInt.java
index 2ac5c4e0..2ac5c4e0 100644
--- a/core_impl/src/main/java/io/opencensus/internal/VarInt.java
+++ b/impl_core/src/main/java/io/opencensus/internal/VarInt.java
diff --git a/core_impl/src/main/java/io/opencensus/internal/package-info.java b/impl_core/src/main/java/io/opencensus/internal/package-info.java
index a9f94864..a9f94864 100644
--- a/core_impl/src/main/java/io/opencensus/internal/package-info.java
+++ b/impl_core/src/main/java/io/opencensus/internal/package-info.java
diff --git a/core_impl/src/main/java/io/opencensus/trace/SpanFactoryImpl.java b/impl_core/src/main/java/io/opencensus/trace/SpanFactoryImpl.java
index d9aadb5e..4e816d97 100644
--- a/core_impl/src/main/java/io/opencensus/trace/SpanFactoryImpl.java
+++ b/impl_core/src/main/java/io/opencensus/trace/SpanFactoryImpl.java
@@ -95,7 +95,7 @@ final class SpanFactoryImpl extends SpanFactory {
       traceOptionsBuilder.setIsSampled();
     }
     TraceOptions traceOptions = traceOptionsBuilder.build();
-    EnumSet<Span.Options> spanOptions = EnumSet.noneOf(Options.class);
+    EnumSet<Options> spanOptions = EnumSet.noneOf(Options.class);
     if (traceOptions.isSampled() || Boolean.TRUE.equals(startSpanOptions.getRecordEvents())) {
       spanOptions.add(Options.RECORD_EVENTS);
     }
diff --git a/core_impl/src/main/java/io/opencensus/trace/SpanImpl.java b/impl_core/src/main/java/io/opencensus/trace/SpanImpl.java
index 269eb767..32992126 100644
--- a/core_impl/src/main/java/io/opencensus/trace/SpanImpl.java
+++ b/impl_core/src/main/java/io/opencensus/trace/SpanImpl.java
@@ -352,7 +352,7 @@ public final class SpanImpl extends Span implements Element<SpanImpl> {
 
   /**
    * Interface to handle the start and end operations for a {@link Span} only when the {@code Span}
-   * has {@link Span.Options#RECORD_EVENTS} option.
+   * has {@link Options#RECORD_EVENTS} option.
    *
    * <p>Implementation must avoid high overhead work in any of the methods because the code is
    * executed on the critical path.
@@ -430,8 +430,8 @@ public final class SpanImpl extends Span implements Element<SpanImpl> {
       this.event = event;
     }
 
-    private SpanData.TimedEvent<T> toSpanDataTimedEvent(TimestampConverter timestampConverter) {
-      return SpanData.TimedEvent.create(timestampConverter.convertNanoTime(nanoTime), event);
+    private TimedEvent<T> toSpanDataTimedEvent(TimestampConverter timestampConverter) {
+      return TimedEvent.create(timestampConverter.convertNanoTime(nanoTime), event);
     }
   }
 
diff --git a/core_impl/src/main/java/io/opencensus/trace/StartEndHandlerImpl.java b/impl_core/src/main/java/io/opencensus/trace/StartEndHandlerImpl.java
index 454f08ee..454f08ee 100644
--- a/core_impl/src/main/java/io/opencensus/trace/StartEndHandlerImpl.java
+++ b/impl_core/src/main/java/io/opencensus/trace/StartEndHandlerImpl.java
diff --git a/core_impl/src/main/java/io/opencensus/trace/TraceComponentImplBase.java b/impl_core/src/main/java/io/opencensus/trace/TraceComponentImplBase.java
index 23a13269..23a13269 100644
--- a/core_impl/src/main/java/io/opencensus/trace/TraceComponentImplBase.java
+++ b/impl_core/src/main/java/io/opencensus/trace/TraceComponentImplBase.java
diff --git a/core_impl/src/main/java/io/opencensus/trace/TracerImpl.java b/impl_core/src/main/java/io/opencensus/trace/TracerImpl.java
index f753a847..f753a847 100644
--- a/core_impl/src/main/java/io/opencensus/trace/TracerImpl.java
+++ b/impl_core/src/main/java/io/opencensus/trace/TracerImpl.java
diff --git a/core_impl/src/main/java/io/opencensus/trace/config/TraceConfigImpl.java b/impl_core/src/main/java/io/opencensus/trace/config/TraceConfigImpl.java
index cf3dc59e..cf3dc59e 100644
--- a/core_impl/src/main/java/io/opencensus/trace/config/TraceConfigImpl.java
+++ b/impl_core/src/main/java/io/opencensus/trace/config/TraceConfigImpl.java
diff --git a/core_impl/src/main/java/io/opencensus/trace/export/ExportComponentImpl.java b/impl_core/src/main/java/io/opencensus/trace/export/ExportComponentImpl.java
index a6286083..a6286083 100644
--- a/core_impl/src/main/java/io/opencensus/trace/export/ExportComponentImpl.java
+++ b/impl_core/src/main/java/io/opencensus/trace/export/ExportComponentImpl.java
diff --git a/core_impl/src/main/java/io/opencensus/trace/export/SpanExporterImpl.java b/impl_core/src/main/java/io/opencensus/trace/export/SpanExporterImpl.java
index 643daae3..643daae3 100644
--- a/core_impl/src/main/java/io/opencensus/trace/export/SpanExporterImpl.java
+++ b/impl_core/src/main/java/io/opencensus/trace/export/SpanExporterImpl.java
diff --git a/core_impl/src/main/java/io/opencensus/trace/internal/ConcurrentIntrusiveList.java b/impl_core/src/main/java/io/opencensus/trace/internal/ConcurrentIntrusiveList.java
index 5b0bc134..5b0bc134 100644
--- a/core_impl/src/main/java/io/opencensus/trace/internal/ConcurrentIntrusiveList.java
+++ b/impl_core/src/main/java/io/opencensus/trace/internal/ConcurrentIntrusiveList.java
diff --git a/core_impl/src/main/java/io/opencensus/trace/internal/RandomHandler.java b/impl_core/src/main/java/io/opencensus/trace/internal/RandomHandler.java
index 8d4060a9..8d4060a9 100644
--- a/core_impl/src/main/java/io/opencensus/trace/internal/RandomHandler.java
+++ b/impl_core/src/main/java/io/opencensus/trace/internal/RandomHandler.java
diff --git a/core_impl/src/main/java/io/opencensus/trace/propagation/BinaryFormatImpl.java b/impl_core/src/main/java/io/opencensus/trace/propagation/BinaryFormatImpl.java
index 890d5821..890d5821 100644
--- a/core_impl/src/main/java/io/opencensus/trace/propagation/BinaryFormatImpl.java
+++ b/impl_core/src/main/java/io/opencensus/trace/propagation/BinaryFormatImpl.java
diff --git a/core_impl/src/main/java/io/opencensus/trace/propagation/PropagationComponentImpl.java b/impl_core/src/main/java/io/opencensus/trace/propagation/PropagationComponentImpl.java
index 144a5639..144a5639 100644
--- a/core_impl/src/main/java/io/opencensus/trace/propagation/PropagationComponentImpl.java
+++ b/impl_core/src/main/java/io/opencensus/trace/propagation/PropagationComponentImpl.java
diff --git a/core_impl/src/test/java/io/opencensus/internal/TimestampConverterTest.java b/impl_core/src/test/java/io/opencensus/internal/TimestampConverterTest.java
index 2fd9612e..2fd9612e 100644
--- a/core_impl/src/test/java/io/opencensus/internal/TimestampConverterTest.java
+++ b/impl_core/src/test/java/io/opencensus/internal/TimestampConverterTest.java
diff --git a/core_impl/src/test/java/io/opencensus/trace/SpanFactoryImplTest.java b/impl_core/src/test/java/io/opencensus/trace/SpanFactoryImplTest.java
index 00d051a6..00d051a6 100644
--- a/core_impl/src/test/java/io/opencensus/trace/SpanFactoryImplTest.java
+++ b/impl_core/src/test/java/io/opencensus/trace/SpanFactoryImplTest.java
diff --git a/core_impl/src/test/java/io/opencensus/trace/SpanImplTest.java b/impl_core/src/test/java/io/opencensus/trace/SpanImplTest.java
index 62052dd2..62052dd2 100644
--- a/core_impl/src/test/java/io/opencensus/trace/SpanImplTest.java
+++ b/impl_core/src/test/java/io/opencensus/trace/SpanImplTest.java
diff --git a/core_impl/src/test/java/io/opencensus/trace/TraceComponentImplBaseTest.java b/impl_core/src/test/java/io/opencensus/trace/TraceComponentImplBaseTest.java
index 9af55910..9af55910 100644
--- a/core_impl/src/test/java/io/opencensus/trace/TraceComponentImplBaseTest.java
+++ b/impl_core/src/test/java/io/opencensus/trace/TraceComponentImplBaseTest.java
diff --git a/core_impl/src/test/java/io/opencensus/trace/config/TraceConfigImplTest.java b/impl_core/src/test/java/io/opencensus/trace/config/TraceConfigImplTest.java
index a76e180f..a76e180f 100644
--- a/core_impl/src/test/java/io/opencensus/trace/config/TraceConfigImplTest.java
+++ b/impl_core/src/test/java/io/opencensus/trace/config/TraceConfigImplTest.java
diff --git a/core_impl/src/test/java/io/opencensus/trace/export/ExportComponentImplTest.java b/impl_core/src/test/java/io/opencensus/trace/export/ExportComponentImplTest.java
index 52e578d5..52e578d5 100644
--- a/core_impl/src/test/java/io/opencensus/trace/export/ExportComponentImplTest.java
+++ b/impl_core/src/test/java/io/opencensus/trace/export/ExportComponentImplTest.java
diff --git a/core_impl/src/test/java/io/opencensus/trace/export/SpanExporterImplTest.java b/impl_core/src/test/java/io/opencensus/trace/export/SpanExporterImplTest.java
index 52251107..52251107 100644
--- a/core_impl/src/test/java/io/opencensus/trace/export/SpanExporterImplTest.java
+++ b/impl_core/src/test/java/io/opencensus/trace/export/SpanExporterImplTest.java
diff --git a/core_impl/src/test/java/io/opencensus/trace/internal/ConcurrentIntrusiveListTest.java b/impl_core/src/test/java/io/opencensus/trace/internal/ConcurrentIntrusiveListTest.java
index d1c13ad0..d1c13ad0 100644
--- a/core_impl/src/test/java/io/opencensus/trace/internal/ConcurrentIntrusiveListTest.java
+++ b/impl_core/src/test/java/io/opencensus/trace/internal/ConcurrentIntrusiveListTest.java
diff --git a/core_impl/src/test/java/io/opencensus/trace/propagation/BinaryFormatImplTest.java b/impl_core/src/test/java/io/opencensus/trace/propagation/BinaryFormatImplTest.java
index 6bc75578..6bc75578 100644
--- a/core_impl/src/test/java/io/opencensus/trace/propagation/BinaryFormatImplTest.java
+++ b/impl_core/src/test/java/io/opencensus/trace/propagation/BinaryFormatImplTest.java
diff --git a/core_impl/src/test/java/io/opencensus/trace/propagation/PropagationComponentImplTest.java b/impl_core/src/test/java/io/opencensus/trace/propagation/PropagationComponentImplTest.java
index dd7812ab..dd7812ab 100644
--- a/core_impl/src/test/java/io/opencensus/trace/propagation/PropagationComponentImplTest.java
+++ b/impl_core/src/test/java/io/opencensus/trace/propagation/PropagationComponentImplTest.java
diff --git a/impl_lite/README.md b/impl_lite/README.md
new file mode 100644
index 00000000..ad7bb9b1
--- /dev/null
+++ b/impl_lite/README.md
@@ -0,0 +1,6 @@
+OpenCensus Android implementation
+======================================================
+
+* Android compatible.
+* StatsManager specifies the stats implementation classes that should be used
+  with Android.
diff --git a/impl_lite/build.gradle b/impl_lite/build.gradle
new file mode 100644
index 00000000..40cce82a
--- /dev/null
+++ b/impl_lite/build.gradle
@@ -0,0 +1,8 @@
+description = 'OpenCensus Lite Implementation'
+
+dependencies {
+    compile project(':opencensus-api'),
+            project(':opencensus-impl-core')
+
+    signature "net.sf.androidscents.signature:android-api-level-14:+@signature"
+}
diff --git a/core_impl_android/src/main/java/io/opencensus/trace/TraceComponentImpl.java b/impl_lite/src/main/java/io/opencensus/trace/TraceComponentImpl.java
index ca806508..ca806508 100644
--- a/core_impl_android/src/main/java/io/opencensus/trace/TraceComponentImpl.java
+++ b/impl_lite/src/main/java/io/opencensus/trace/TraceComponentImpl.java
diff --git a/core_impl_android/src/test/java/io/opencensus/trace/TraceComponentImplTest.java b/impl_lite/src/test/java/io/opencensus/trace/TraceComponentImplTest.java
index 024e8692..024e8692 100644
--- a/core_impl_android/src/test/java/io/opencensus/trace/TraceComponentImplTest.java
+++ b/impl_lite/src/test/java/io/opencensus/trace/TraceComponentImplTest.java
diff --git a/settings.gradle b/settings.gradle
index ade14ea5..e7a8c4c4 100644
--- a/settings.gradle
+++ b/settings.gradle
@@ -1,6 +1,9 @@
-rootProject.name = "instrumentation-java"
+rootProject.name = "opencensus-java"
 
 include ":opencensus-api"
+include ":opencensus-impl-core"
+include ":opencensus-impl-lite"
+include ":opencensus-impl"
 include ":all"
 include ":core"
 include ":core_impl"
@@ -8,6 +11,9 @@ include ":core_impl_java"
 include ":core_impl_android"
 
 project(':opencensus-api').projectDir = "$rootDir/api" as File
+project(':opencensus-impl-core').projectDir = "$rootDir/impl_core" as File
+project(':opencensus-impl-lite').projectDir = "$rootDir/impl_lite" as File
+project(':opencensus-impl').projectDir = "$rootDir/impl" as File
 
 // Java8 projects only
 if (JavaVersion.current().isJava8Compatible()) {