Make "./gradlew goJF" work in examples/ (#1059)

2 files changed, 50 insertions, 11 deletions

diff --git a/examples/build.gradle b/examples/build.gradle
index fe72d75a..ab5de34a 100644
--- a/examples/build.gradle
+++ b/examples/build.gradle
@@ -1,8 +1,25 @@
 description = 'OpenCensus Examples'
 
-apply plugin: "checkstyle"
+buildscript {
+    repositories {
+        mavenCentral()
+        mavenLocal()
+        maven {
+            url "https://plugins.gradle.org/m2/"
+        }
+    }
+    dependencies {
+        classpath "gradle.plugin.com.github.sherter.google-java-format:google-java-format-gradle-plugin:0.6"
+    }
+}
+
+apply plugin: 'checkstyle'
 apply plugin: 'idea'
 apply plugin: 'java'
+// Plugins that require java8
+if (JavaVersion.current().isJava8Compatible()) {
+    apply plugin: 'com.github.sherter.google-java-format'
+}
 
 repositories {
     mavenCentral()
@@ -24,6 +41,25 @@ checkstyle {
     configProperties["rootDir"] = file("$rootDir/../")
 }
 
+// Google formatter works only on java8.
+if (JavaVersion.current().isJava8Compatible()) {
+    googleJavaFormat {
+        toolVersion '1.5'
+    }
+
+    afterEvaluate {  // Allow subproject to add more source sets.
+        tasks.googleJavaFormat {
+            source = sourceSets*.allJava
+            include '**/*.java'
+        }
+
+        tasks.verifyGoogleJavaFormat {
+            source = sourceSets*.allJava
+            include '**/*.java'
+        }
+    }
+}
+
 tasks.withType(JavaCompile) {
     sourceCompatibility = '1.8'
     targetCompatibility = '1.8'
diff --git a/examples/src/main/java/io/opencensus/examples/helloworld/QuickStart.java b/examples/src/main/java/io/opencensus/examples/helloworld/QuickStart.java
index f6626135..2ff505ee 100644
--- a/examples/src/main/java/io/opencensus/examples/helloworld/QuickStart.java
+++ b/examples/src/main/java/io/opencensus/examples/helloworld/QuickStart.java
@@ -56,27 +56,30 @@ public final class QuickStart {
   private static final TagKey FRONTEND_KEY = TagKey.create("my.org/keys/frontend");
 
   // videoSize will measure the size of processed videos.
-  private static final MeasureLong VIDEO_SIZE = MeasureLong.create(
-      "my.org/measure/video_size", "size of processed videos", "MBy");
+  private static final MeasureLong VIDEO_SIZE =
+      MeasureLong.create("my.org/measure/video_size", "size of processed videos", "MBy");
 
   // Create view to see the processed video size distribution broken down by frontend.
   // The view has bucket boundaries (0, 256, 65536) that will group measure values into
   // histogram buckets.
   private static final View.Name VIDEO_SIZE_VIEW_NAME = View.Name.create("my.org/views/video_size");
-  private static final View VIDEO_SIZE_VIEW = View.create(
-      VIDEO_SIZE_VIEW_NAME,
-      "processed video size over time",
-      VIDEO_SIZE,
-      Aggregation.Distribution.create(BucketBoundaries.create(Arrays.asList(0.0, 256.0, 65536.0))),
-      Collections.singletonList(FRONTEND_KEY),
-      Cumulative.create());
+  private static final View VIDEO_SIZE_VIEW =
+      View.create(
+          VIDEO_SIZE_VIEW_NAME,
+          "processed video size over time",
+          VIDEO_SIZE,
+          Aggregation.Distribution.create(
+              BucketBoundaries.create(Arrays.asList(0.0, 256.0, 65536.0))),
+          Collections.singletonList(FRONTEND_KEY),
+          Cumulative.create());
 
   /** Main launcher for the QuickStart example. */
   public static void main(String[] args) throws InterruptedException {
     TagContextBuilder tagContextBuilder =
         tagger.currentBuilder().put(FRONTEND_KEY, TagValue.create("mobile-ios9.3.5"));
     SpanBuilder spanBuilder =
-        tracer.spanBuilder("my.org/ProcessVideo")
+        tracer
+            .spanBuilder("my.org/ProcessVideo")
             .setRecordEvents(true)
             .setSampler(Samplers.alwaysSample());
     viewManager.registerView(VIDEO_SIZE_VIEW);