Added probe to determine if data reduction proxy can be used

chrome/android/java/src/org/chromium/chrome/browser/net/spdyproxy/DataReductionProxySettingsAndroid.java

Index: chrome/android/java/src/org/chromium/chrome/browser/net/spdyproxy/DataReductionProxySettingsAndroid.java
diff --git a/chrome/android/java/src/org/chromium/chrome/browser/net/spdyproxy/DataReductionProxySettingsAndroid.java b/chrome/android/java/src/org/chromium/chrome/browser/net/spdyproxy/DataReductionProxySettingsAndroid.java
new file mode 100644
index 0000000000000000000000000000000000000000..2dace66fe2628bb07258f28ac9e91c2abfd73427
--- /dev/null
+++ b/chrome/android/java/src/org/chromium/chrome/browser/net/spdyproxy/DataReductionProxySettingsAndroid.java
@@ -0,0 +1,173 @@
+// Copyright (c) 2013 The Chromium Authors. All rights reserved.

[nyquist, 2013/09/04 02:20:15]

Nit: Nowadays, there should be no (c), but the year stays.

[bengr, 2013/09/05 02:03:49]

Done.

+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+package org.chromium.chrome.browser.net.spdyproxy;
+
+import org.chromium.base.CalledByNative;
+import org.chromium.base.ThreadUtils;
+
+public class DataReductionProxySettingsAndroid {
+
+    public static class ContentLengths {
+        private final long mOriginal;
+        private final long mReceived;
+
+        @CalledByNative("ContentLengths")
+        public static ContentLengths create(long original, long received) {
+            return new ContentLengths(original, received);
+        }
+
+        public ContentLengths(long original, long received) {

[nyquist, 2013/09/04 02:20:15]

private

[bengr, 2013/09/05 02:03:49]

Done.

+            mOriginal = original;
+            mReceived = received;
+        }
+
+        public long getOriginal() {
+            return mOriginal;
+        }
+
+        public long getReceived() {
+            return mReceived;
+        }
+    }
+
+    private static DataReductionProxySettingsAndroid sConfig;

[nyquist, 2013/09/04 02:20:15]

sSettings? At least something that is part of the class name, or you could of
course use something generic like sInstance.

[bengr, 2013/09/05 02:03:49]

Done.

+
+    public static DataReductionProxySettingsAndroid getInstance() {
+        ThreadUtils.assertOnUiThread();
+        if (sConfig == null) {
+            sConfig = new DataReductionProxySettingsAndroid();
+        }
+        return sConfig;
+    }
+
+    private final int mNativeDataReductionProxySettingsAndroid;
+
+    private DataReductionProxySettingsAndroid() {
+        // Note that this technically leaks the native object, however,
+        // DataReductionProxySettingsAndroid is a singleton that lives forever and there's no clean
+        // shutdown of Chrome on Android
+        mNativeDataReductionProxySettingsAndroid = nativeInit();
+        initDataReductionProxySettings();
+    }
+
+    /**
+     * Initializes the data reduction proxy at Chrome startup.
+     */
+    public void initDataReductionProxySettings() {
+        nativeInitDataReductionProxySettings(mNativeDataReductionProxySettingsAndroid);
+    }
+
+
+    /** Returns true if the SPDY proxy is meant to be available. */
+    public boolean isDataReductionProxyAvailable() {
+        return nativeIsDataReductionProxyAvailable(mNativeDataReductionProxySettingsAndroid);
+    }
+
+    /** Returns true if the SPDY proxy promo is meant to be available. */
+    public boolean isDataReductionProxyPromoAvailable() {
+        return nativeIsDataReductionProxyPromoAvailable(mNativeDataReductionProxySettingsAndroid);
+    }
+
+    /**
+     * Returns the current SPDY proxy origin.
+     */
+    public String getDataReductionProxyOrigin() {
+        return nativeGetDataReductionProxyOrigin(mNativeDataReductionProxySettingsAndroid);
+    }
+
+    /*
+     * Returns the current SPDY proxy property.
+     */
+    public String getDataReductionProxyValue() {
+        return nativeGetDataReductionProxyValue(mNativeDataReductionProxySettingsAndroid);
+    }
+
+    /**
+     * Sets the preference on whether to enable/disable the SPDY proxy. This will zero out the
+     * data reduction statistics if this is the first time the SPDY proxy has been enabled.
+     */
+    public void setDataReductionProxyEnabled(boolean enabled) {
+        nativeSetDataReductionProxyEnabled(mNativeDataReductionProxySettingsAndroid, enabled);
+    }
+
+    /** Returns true if the SPDY proxy is enabled. */
+    public boolean isDataReductionProxyEnabled() {
+        return nativeIsDataReductionProxyEnabled(mNativeDataReductionProxySettingsAndroid);
+    }
+
+    /**
+     * Returns the time that the data reduction statistics were last updated.
+     * @return The last update time in milliseconds since the epoch.
+     */
+    public long getDataReductionLastUpdateTime()  {
+        return nativeGetDataReductionLastUpdateTime(mNativeDataReductionProxySettingsAndroid);
+    }
+
+    /**
+     * Returns aggregate original and received content lengths.
+     * @return The content lengths.
+     */
+    public ContentLengths getContentLengths() {
+        return nativeGetContentLengths(mNativeDataReductionProxySettingsAndroid);
+    }
+
+    /**
+     * Retrieves the history of daily totals of bytes that would have been
+     * received if no data reducing mechanism had been applied.
+     * @param days The number of days of history to get
+     * @return The history of daily totals
+     */
+    public long[] getOriginalNetworkStatsHistory(int days) {

[nyquist, 2013/09/04 02:20:15]

|days| is unused. something that will be used soon?

[bengr, 2013/09/05 02:03:49]

Done.

+        return nativeGetDailyOriginalContentLengths(mNativeDataReductionProxySettingsAndroid);
+    }
+
+    /**
+     * Retrieves the history of daily totals of bytes that were received after
+     * applying a data reducing mechanism.
+     * @param days The number of days of history to get
+     * @return The history of daily totals
+     */
+    public long[] getReceivedNetworkStatsHistory(int days) {

[nyquist, 2013/09/04 02:20:15]

|days| is unused.

[bengr, 2013/09/05 02:03:49]

Done.

+        return nativeGetDailyReceivedContentLengths(mNativeDataReductionProxySettingsAndroid);
+    }
+
+    /**
+     * @return The data reduction settings as a string percentage.
+     */
+    public String getContentLengthPercentSavings() {
+        ContentLengths length = getContentLengths();
+        String percent = "0%";
+        if (length.getOriginal() > 0L  && length.getOriginal() > length.getReceived()) {
+            percent = String.format(
+                    "%.0f%%", 100.0 *
+                    (length.getOriginal() - length.getReceived()) / length.getOriginal());
+        }
+        return percent;
+    }
+
+    private native int nativeInit();
+    private native void nativeInitDataReductionProxySettings(
+            int nativeDataReductionProxySettingsAndroid);
+    private native boolean nativeIsDataReductionProxyAvailable(
+            int nativeDataReductionProxySettingsAndroid);
+    private native boolean nativeIsDataReductionProxyPromoAvailable(
+            int nativeDataReductionProxySettingsAndroid);
+    private native String nativeGetDataReductionProxyOrigin(
+            int nativeDataReductionProxySettingsAndroid);
+    private native String nativeGetDataReductionProxyValue(
+            int nativeDataReductionProxySettingsAndroid);
+    private native boolean nativeIsDataReductionProxyEnabled(
+            int nativeDataReductionProxySettingsAndroid);
+    private native void nativeSetDataReductionProxyEnabled(
+            int nativeDataReductionProxySettingsAndroid, boolean enabled);
+    private native long nativeGetDataReductionLastUpdateTime(
+            int nativeDataReductionProxySettingsAndroid);
+    private native ContentLengths nativeGetContentLengths(
+            int nativeDataReductionProxySettingsAndroid);
+    private native long[] nativeGetDailyOriginalContentLengths(
+            int nativeDataReductionProxySettingsAndroid);
+    private native long[] nativeGetDailyReceivedContentLengths(
+            int nativeDataReductionProxySettingsAndroid);
+}