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diff --git a/core/java/android/util/TimingLogger.java b/core/java/android/util/TimingLogger.java
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+++ b/core/java/android/util/TimingLogger.java
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+/*
+ * Copyright (C) 2007 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 android.util;
+
+import java.util.ArrayList;
+
+import android.os.SystemClock;
+
+/**
+ * A utility class to help log timings splits throughout a method call.
+ * Typical usage is:
+ *
+ * TimingLogger timings = new TimingLogger(TAG, "methodA");
+ * ... do some work A ...
+ * timings.addSplit("work A");
+ * ... do some work B ...
+ * timings.addSplit("work B");
+ * ... do some work C ...
+ * timings.addSplit("work C");
+ * timings.dumpToLog();
+ *
+ * The dumpToLog call would add the following to the log:
+ *
+ * D/TAG     ( 3459): methodA: begin
+ * D/TAG     ( 3459): methodA:      9 ms, work A
+ * D/TAG     ( 3459): methodA:      1 ms, work B
+ * D/TAG     ( 3459): methodA:      6 ms, work C
+ * D/TAG     ( 3459): methodA: end, 16 ms
+ */
+public class TimingLogger {
+
+    /**
+     * The Log tag to use for checking Log.isLoggable and for
+     * logging the timings.
+     */
+    private String mTag;
+
+    /** A label to be included in every log. */
+    private String mLabel;
+
+    /** Used to track whether Log.isLoggable was enabled at reset time. */
+    private boolean mDisabled;
+
+    /** Stores the time of each split. */
+    ArrayList<Long> mSplits;
+
+    /** Stores the labels for each split. */
+    ArrayList<String> mSplitLabels;
+
+    /**
+     * Create and initialize a TimingLogger object that will log using
+     * the specific tag. If the Log.isLoggable is not enabled to at
+     * least the Log.VERBOSE level for that tag at creation time then
+     * the addSplit and dumpToLog call will do nothing.
+     * @param tag the log tag to use while logging the timings
+     * @param label a string to be displayed with each log
+     */
+    public TimingLogger(String tag, String label) {
+        reset(tag, label);
+    }
+
+    /**
+     * Clear and initialize a TimingLogger object that will log using
+     * the specific tag. If the Log.isLoggable is not enabled to at
+     * least the Log.VERBOSE level for that tag at creation time then
+     * the addSplit and dumpToLog call will do nothing.
+     * @param tag the log tag to use while logging the timings
+     * @param label a string to be displayed with each log
+     */
+    public void reset(String tag, String label) {
+        mTag = tag;
+        mLabel = label;
+        reset();
+    }
+
+    /**
+     * Clear and initialize a TimingLogger object that will log using
+     * the tag and label that was specified previously, either via
+     * the constructor or a call to reset(tag, label). If the
+     * Log.isLoggable is not enabled to at least the Log.VERBOSE
+     * level for that tag at creation time then the addSplit and
+     * dumpToLog call will do nothing.
+     */
+    public void reset() {
+        mDisabled = !Log.isLoggable(mTag, Log.VERBOSE);
+        if (mDisabled) return;
+        if (mSplits == null) {
+            mSplits = new ArrayList<Long>();
+            mSplitLabels = new ArrayList<String>();
+        } else {
+            mSplits.clear();
+            mSplitLabels.clear();
+        }
+        addSplit(null);
+    }
+
+    /**
+     * Add a split for the current time, labeled with splitLabel. If
+     * Log.isLoggable was not enabled to at least the Log.VERBOSE for
+     * the specified tag at construction or reset() time then this
+     * call does nothing.
+     * @param splitLabel a label to associate with this split.
+     */
+    public void addSplit(String splitLabel) {
+        if (mDisabled) return;
+        long now = SystemClock.elapsedRealtime();
+        mSplits.add(now);
+        mSplitLabels.add(splitLabel);
+    }
+
+    /**
+     * Dumps the timings to the log using Log.d(). If Log.isLoggable was
+     * not enabled to at least the Log.VERBOSE for the specified tag at
+     * construction or reset() time then this call does nothing.
+     */
+    public void dumpToLog() {
+        if (mDisabled) return;
+        Log.d(mTag, mLabel + ": begin");
+        final long first = mSplits.get(0);
+        long now = first;
+        for (int i = 1; i < mSplits.size(); i++) {
+            now = mSplits.get(i);
+            final String splitLabel = mSplitLabels.get(i);
+            final long prev = mSplits.get(i - 1);
+
+            Log.d(mTag, mLabel + ":      " + (now - prev) + " ms, " + splitLabel);
+        }
+        Log.d(mTag, mLabel + ": end, " + (now - first) + " ms");
+    }
+}