1 files changed, 100 insertions, 0 deletions
diff --git a/java/com/android/contacts/common/util/StopWatch.java b/java/com/android/contacts/common/util/StopWatch.java
new file mode 100644
index 000000000..b944b9867
--- /dev/null
+++ b/java/com/android/contacts/common/util/StopWatch.java
@@ -0,0 +1,100 @@
+/*
+ * Copyright (C) 2012 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.contacts.common.util;
+
+import android.util.Log;
+import java.util.ArrayList;
+
+/** A {@link StopWatch} records start, laps and stop, and print them to logcat. */
+public class StopWatch {
+
+  private final String mLabel;
+
+  private final ArrayList<Long> mTimes = new ArrayList<>();
+  private final ArrayList<String> mLapLabels = new ArrayList<>();
+
+  private StopWatch(String label) {
+    mLabel = label;
+    lap("");
+  }
+
+  /** Create a new instance and start it. */
+  public static StopWatch start(String label) {
+    return new StopWatch(label);
+  }
+
+  /** Return a dummy instance that does no operations. */
+  public static StopWatch getNullStopWatch() {
+    return NullStopWatch.INSTANCE;
+  }
+
+  /** Record a lap. */
+  public void lap(String lapLabel) {
+    mTimes.add(System.currentTimeMillis());
+    mLapLabels.add(lapLabel);
+  }
+
+  /** Stop it and log the result, if the total time >= {@code timeThresholdToLog}. */
+  public void stopAndLog(String TAG, int timeThresholdToLog) {
+
+    lap("");
+
+    final long start = mTimes.get(0);
+    final long stop = mTimes.get(mTimes.size() - 1);
+
+    final long total = stop - start;
+    if (total < timeThresholdToLog) {
+      return;
+    }
+
+    final StringBuilder sb = new StringBuilder();
+    sb.append(mLabel);
+    sb.append(",");
+    sb.append(total);
+    sb.append(": ");
+
+    long last = start;
+    for (int i = 1; i < mTimes.size(); i++) {
+      final long current = mTimes.get(i);
+      sb.append(mLapLabels.get(i));
+      sb.append(",");
+      sb.append((current - last));
+      sb.append(" ");
+      last = current;
+    }
+    Log.v(TAG, sb.toString());
+  }
+
+  private static class NullStopWatch extends StopWatch {
+
+    public static final NullStopWatch INSTANCE = new NullStopWatch();
+
+    public NullStopWatch() {
+      super(null);
+    }
+
+    @Override
+    public void lap(String lapLabel) {
+      // noop
+    }
+
+    @Override
+    public void stopAndLog(String TAG, int timeThresholdToLog) {
+      // noop
+    }
+  }
+}