Adds JSON serializers for swingp stats.

This CL adds JSON serialization of captured Swing rendering stats using the
GSON library.
The serialized JSON can eventually be read by, say, a browser, and replay what
was captured by swingp.

Change-Id: I33f1483f0e1eba6dc4965f3efb2b7d4c8bc1cd46
Test: Added tests for serialization and main serialized stat getter.
Bug: 80499904

2 files changed, 118 insertions, 12 deletions

diff --git a/swingp/testSrc/com/android/tools/swingp/MethodStatTest.java b/swingp/testSrc/com/android/tools/swingp/MethodStatTest.java
index 53a9afb8ae4..0438d81dc6f 100644
--- a/swingp/testSrc/com/android/tools/swingp/MethodStatTest.java
+++ b/swingp/testSrc/com/android/tools/swingp/MethodStatTest.java
@@ -16,31 +16,41 @@
 package com.android.tools.swingp;
 
 import org.jetbrains.annotations.NotNull;
-import org.junit.After;
-import org.junit.Before;
+import com.google.common.truth.Truth;
+import com.google.gson.JsonArray;
 import org.junit.Test;
 
 public class MethodStatTest {
-  @Before
-  public void before() {
-    RenderStatsManager.setIsEnabled(true);
-  }
-
-  @After
-  public void after() {
-    RenderStatsManager.setIsEnabled(false);
-  }
-
   @Test(expected = RuntimeException.class)
   public void catchesDoubleEnd() {
+    RenderStatsManager.setIsEnabled(true);
     BadTestClass bad = new BadTestClass();
     bad.doubleBad();
+    RenderStatsManager.setIsEnabled(false);
   }
 
   @Test
   public void methodStatEndsCorrect() {
+    RenderStatsManager.setIsEnabled(true);
     TestClass good = new TestClass();
     good.foo();
+    RenderStatsManager.setIsEnabled(false);
+  }
+
+  @Test
+  public void arraySerializesCorrectly() {
+    int[] intArray = {5, 7};
+    JsonArray jsonIntArray = SerializationHelpers.arrayToJsonArray(intArray);
+    Truth.assertThat(jsonIntArray.size()).isEqualTo(2);
+    Truth.assertThat(jsonIntArray.get(0).getAsInt()).isEqualTo(intArray[0]);
+    Truth.assertThat(jsonIntArray.get(1).getAsInt()).isEqualTo(intArray[1]);
+
+    double[] doubleArray = {3.5, 9.5, 11};
+    JsonArray jsonDoubleArray = SerializationHelpers.arrayToJsonArray(doubleArray);
+    Truth.assertThat(jsonDoubleArray.size()).isEqualTo(3);
+    Truth.assertThat(jsonDoubleArray.get(0).getAsDouble()).isEqualTo(doubleArray[0]);
+    Truth.assertThat(jsonDoubleArray.get(1).getAsDouble()).isEqualTo(doubleArray[1]);
+    Truth.assertThat(jsonDoubleArray.get(2).getAsDouble()).isEqualTo(doubleArray[2]);
   }
 
   /**
diff --git a/swingp/testSrc/com/android/tools/swingp/RenderStatsManagerTest.java b/swingp/testSrc/com/android/tools/swingp/RenderStatsManagerTest.java
new file mode 100644
index 00000000000..8e10fceb063
--- /dev/null
+++ b/swingp/testSrc/com/android/tools/swingp/RenderStatsManagerTest.java
@@ -0,0 +1,96 @@
+/*
+ * Copyright (C) 2018 The Android Open Source Project
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+package com.android.tools.swingp;
+
+import com.google.gson.JsonArray;
+import com.google.gson.JsonElement;
+import com.google.gson.JsonNull;
+import com.google.gson.JsonObject;
+import org.jetbrains.annotations.NotNull;
+import org.junit.Test;
+
+import java.util.HashSet;
+import java.util.Set;
+
+import static com.google.common.truth.Truth.assertThat;
+
+public class RenderStatsManagerTest {
+  @Test
+  public void getsNullForEmptyOrDisabled() {
+    // Ensure empty stats returns JsonNull.
+    assertThat(RenderStatsManager.getJson()).isSameAs(JsonNull.INSTANCE);
+
+    // Ensure JsonNull is returned when the system is disabled.
+    MethodStat fakeStat = new TestMethodStat(this);
+    fakeStat.endMethod();
+    assertThat(RenderStatsManager.getJson()).isSameAs(JsonNull.INSTANCE);
+  }
+
+  @Test
+  public void getsCorrectThreads() throws InterruptedException {
+    RenderStatsManager.setIsEnabled(true);
+
+    MethodStat fakeStat = new TestMethodStat(this);
+    fakeStat.endMethod();
+
+    String separateThreadName = "Separate Thread";
+    Thread separateThread = new Thread(separateThreadName) {
+      @Override
+      public void run() {
+        super.run();
+
+        MethodStat separateStat = new TestMethodStat(this);
+        separateStat.endMethod();
+      }
+    };
+    separateThread.start();
+    separateThread.join();
+
+    JsonElement element = RenderStatsManager.getJson();
+    assertThat(element).isNotSameAs(JsonNull.INSTANCE);
+    assertThat(element.isJsonArray()).isTrue();
+
+    JsonArray root = (JsonArray)element;
+    assertThat(root.size()).isEqualTo(2);
+
+    assertThat(root.get(0).isJsonObject()).isTrue();
+    JsonElement currentThreadElement = ((JsonObject)root.get(0)).get("__tName");
+    assertThat(currentThreadElement.isJsonPrimitive()).isTrue();
+
+    assertThat(root.get(1).isJsonObject()).isTrue();
+    JsonElement separateThreadElement = ((JsonObject)root.get(1)).get("__tName");
+    assertThat(separateThreadElement.isJsonPrimitive()).isTrue();
+
+    Set<String> threadNames = new HashSet<>();
+    threadNames.add(currentThreadElement.getAsString());
+    threadNames.add(separateThreadElement.getAsString());
+    assertThat(threadNames).containsExactly(Thread.currentThread().getName(), separateThreadName);
+
+    // Ensure there are no leftovers.
+    assertThat(RenderStatsManager.getJson()).isSameAs(JsonNull.INSTANCE);
+
+    RenderStatsManager.setIsEnabled(false);
+  }
+
+  /**
+   * Trivial extension of {@link MethodStat} (since it's abstract) to test its implementation.
+   */
+  private static final class TestMethodStat extends MethodStat {
+    public TestMethodStat(@NotNull Object owner) {
+      super(owner);
+    }
+  }
+}