1 files changed, 73 insertions, 0 deletions
diff --git a/src/tools/android/java/com/google/devtools/build/android/InMemoryProfiler.java b/src/tools/android/java/com/google/devtools/build/android/InMemoryProfiler.java
new file mode 100644
index 0000000000..3032280430
--- /dev/null
+++ b/src/tools/android/java/com/google/devtools/build/android/InMemoryProfiler.java
@@ -0,0 +1,73 @@
+// Copyright 2017 The Bazel Authors. All rights reserved.
+//
+// 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.google.devtools.build.android;
+
+import static java.util.stream.Collectors.joining;
+
+import com.google.common.base.Preconditions;
+import com.google.common.base.Stopwatch;
+import java.util.ArrayList;
+import java.util.HashMap;
+import java.util.List;
+import java.util.Map;
+
+/** Logs timing data to an in memory list that can be dumped. */
+public class InMemoryProfiler implements Profiler {
+
+  private final Map<String, Stopwatch> tasks = new HashMap<>();
+  private final List<Timing> report = new ArrayList<>();
+
+  private InMemoryProfiler() {}
+
+  public static InMemoryProfiler createAndStart(String taskName) {
+    final InMemoryProfiler profiler = new InMemoryProfiler();
+    return profiler.startTask(taskName);
+  }
+
+  @Override
+  public InMemoryProfiler startTask(String taskName) {
+    Preconditions.checkArgument(!tasks.containsKey(taskName));
+    tasks.put(taskName, Stopwatch.createStarted());
+    return this;
+  }
+
+  @Override
+  public InMemoryProfiler recordEndOf(String taskName) {
+    Preconditions.checkArgument(tasks.containsKey(taskName));
+    final Stopwatch task = tasks.remove(taskName);
+    report.add(new Timing(taskName, task.elapsed().toMillis() / 1000f));
+    return this;
+  }
+
+  public String asTimingReport() {
+    return report.stream().map(Timing::toString).collect(joining("\n"));
+  }
+
+  static final class Timing {
+
+    private final String taskName;
+    private final float seconds;
+
+    Timing(String taskName, float seconds) {
+      this.taskName = taskName;
+      this.seconds = seconds;
+    }
+
+    @Override
+    public String toString() {
+      return String.format("%s in %,.2fs", taskName, seconds);
+    }
+  }
+}