Bug 753312 - Extract a PrefsHelper class that manages getting/setting of gecko prefs, and updated existing code to use it. r=cpeterson

mobile/android/base/GeckoPreferences.java

@@ -8,14 +8,12 @@ package org.mozilla.gecko;
 import org.mozilla.gecko.util.GeckoEventListener;
 
 import org.json.JSONArray;
-import org.json.JSONException;
 import org.json.JSONObject;
 
 import android.app.AlertDialog;
 import android.app.Dialog;
 import android.content.Context;
 import android.content.DialogInterface;
-import android.content.res.Configuration;
 import android.os.Bundle;
 import android.preference.CheckBoxPreference;
 import android.preference.EditTextPreference;
@@ -53,7 +51,6 @@ public class GeckoPreferences
     protected void onCreate(Bundle savedInstanceState) {
         super.onCreate(savedInstanceState);
         addPreferencesFromResource(R.xml.preferences);
-        registerEventListener("Preferences:Data");
         registerEventListener("Sanitize:Finished");
     }
 
@@ -71,16 +68,12 @@ public class GeckoPreferences
     @Override
     protected void onDestroy() {
         super.onDestroy();
-        unregisterEventListener("Preferences:Data");
         unregisterEventListener("Sanitize:Finished");
     }
 
     public void handleMessage(String event, JSONObject message) {
         try {
-            if (event.equals("Preferences:Data")) {
+            if (event.equals("Sanitize:Finished")) {
-                JSONArray jsonPrefs = message.getJSONArray("preferences");
-                refresh(jsonPrefs);
-            } else if (event.equals("Sanitize:Finished")) {
                 boolean success = message.getBoolean("success");
                 final int stringRes = success ? R.string.private_data_success : R.string.private_data_fail;
                 final Context context = this;
@@ -95,14 +88,6 @@ public class GeckoPreferences
         }
     }
 
-    // Initialize preferences by sending the "Preferences:Get" command to Gecko
-    private void initValues() {
-        JSONArray jsonPrefs = new JSONArray(mPreferencesList);
-
-        GeckoEvent event = GeckoEvent.createBroadcastEvent("Preferences:Get", jsonPrefs.toString());
-        GeckoAppShell.sendEventToGecko(event);
-    }
-
     private void initGroups(PreferenceGroup preferences) {
         final int count = preferences.getPreferenceCount();
         for (int i = 0; i < count; i++) {
@@ -158,7 +143,9 @@ public class GeckoPreferences
             setCharEncodingState(((String) newValue).equals("true"));
         }
 
-        setPreference(prefName, newValue);
+        if (!TextUtils.isEmpty(prefName)) {
+            PrefsHelper.setPref(prefName, newValue);
+        }
         if (preference instanceof ListPreference) {
             // We need to find the entry for the new value
             int newIndex = ((ListPreference)preference).findIndexOfValue((String) newValue);
@@ -266,18 +253,7 @@ public class GeckoPreferences
                        .setView((View)linearLayout)
                        .setPositiveButton(R.string.button_ok, new DialogInterface.OnClickListener() {  
                             public void onClick(DialogInterface dialog, int which) {
-                                try {
+                                PrefsHelper.setPref("privacy.masterpassword.enabled", input.getText().toString());
-                                    JSONObject jsonPref = new JSONObject();
-                                    jsonPref.put("name", "privacy.masterpassword.enabled");
-                                    jsonPref.put("type", "string");
-                                    jsonPref.put("value", input.getText().toString());
-                        
-                                    GeckoEvent event = GeckoEvent.createBroadcastEvent("Preferences:Set", jsonPref.toString());
-                                    GeckoAppShell.sendEventToGecko(event);
-                                } catch(Exception ex) {
-                                    Log.e(LOGTAG, "Error setting masterpassword", ex);
-                                }
-                                return;
                             }
                         })
                         .setNegativeButton(R.string.button_cancel, new DialogInterface.OnClickListener() {  
@@ -299,42 +275,35 @@ public class GeckoPreferences
         return dialog;
     }
 
-    private void refresh(JSONArray jsonPrefs) {
+    // Initialize preferences by requesting the preference values from Gecko
-        // enable all preferences once we have them from gecko
+    private void initValues() {
-        GeckoAppShell.getMainHandler().post(new Runnable() {
+        JSONArray jsonPrefs = new JSONArray(mPreferencesList);
-            public void run() {
+        PrefsHelper.getPrefs(jsonPrefs, new PrefsHelper.PrefHandlerBase() {
-                mPreferenceScreen.setEnabled(true);
+            private Preference getField(String prefName) {
+                return (mPreferenceScreen == null ? null : mPreferenceScreen.findPreference(prefName));
             }
-        });
 
-        try {
+            @Override public void prefValue(String prefName, final boolean value) {
-            if (mPreferenceScreen == null)
+                final Preference pref = getField(prefName);
-                return;
+                if (pref instanceof CheckBoxPreference) {
-
-            final int length = jsonPrefs.length();
-            for (int i = 0; i < length; i++) {
-                JSONObject jPref = jsonPrefs.getJSONObject(i);
-                final String prefName = jPref.getString("name");
-                final String prefType = jPref.getString("type");
-                final Preference pref = mPreferenceScreen.findPreference(prefName);
-
-                if (pref instanceof CheckBoxPreference && "bool".equals(prefType)) {
-                    final boolean value = jPref.getBoolean("value");
                     GeckoAppShell.getMainHandler().post(new Runnable() {
                         public void run() {
                             if (((CheckBoxPreference)pref).isChecked() != value)
                                 ((CheckBoxPreference)pref).setChecked(value);
                         }
                     });
-                } else if (pref instanceof EditTextPreference && "string".equals(prefType)) {
+                }
-                    final String value = jPref.getString("value");
+            }
+
+            @Override public void prefValue(String prefName, final String value) {
+                final Preference pref = getField(prefName);
+                if (pref instanceof EditTextPreference) {
                     GeckoAppShell.getMainHandler().post(new Runnable() {
                         public void run() {
                             ((EditTextPreference)pref).setText(value);
                         }
                     });
-                } else if (pref instanceof ListPreference && "string".equals(prefType)) {
+                } else if (pref instanceof ListPreference) {
-                    final String value = jPref.getString("value");
                     GeckoAppShell.getMainHandler().post(new Runnable() {
                         public void run() {
                             ((ListPreference)pref).setValue(value);
@@ -345,8 +314,7 @@ public class GeckoPreferences
                     });
                 } else if (pref instanceof FontSizePreference) {
                     final FontSizePreference fontSizePref = (FontSizePreference) pref;
-                    final String twipValue = jPref.getString("value");
+                    fontSizePref.setSavedFontSize(value);
-                    fontSizePref.setSavedFontSize(twipValue);
                     final String fontSizeName = fontSizePref.getSavedFontSizeName();
                     GeckoAppShell.getMainHandler().post(new Runnable() {
                         public void run() {
@@ -354,39 +322,17 @@ public class GeckoPreferences
                         }
                     });
                 }
-
-            }
-        } catch (JSONException e) {
-            Log.e(LOGTAG, "Problem parsing preferences response: ", e);
-        }
             }
 
-    // send the Preferences:Set message to Gecko
+            @Override public void finish() {
-    public static void setPreference(String pref, Object value) {
+                // enable all preferences once we have them from gecko
-        if (pref == null || pref.length() == 0)
+                GeckoAppShell.getMainHandler().post(new Runnable() {
-            return;
+                    public void run() {
-
+                        mPreferenceScreen.setEnabled(true);
-        try {
-            JSONObject jsonPref = new JSONObject();
-            jsonPref.put("name", pref);
-            if (value instanceof Boolean) {
-                jsonPref.put("type", "bool");
-                jsonPref.put("value", ((Boolean)value).booleanValue());
                     }
-            else if (value instanceof Integer) {
+                });
-                jsonPref.put("type", "int");
-                jsonPref.put("value", ((Integer)value).intValue());
-            }
-            else {
-                jsonPref.put("type", "string");
-                jsonPref.put("value", String.valueOf(value));
-            }
-
-            GeckoEvent event = GeckoEvent.createBroadcastEvent("Preferences:Set", jsonPref.toString());
-            GeckoAppShell.sendEventToGecko(event);
-        } catch (JSONException e) {
-            Log.e(LOGTAG, "JSON exception: ", e);
             }
+        });
     }
 
     private void registerEventListener(String event) {

mobile/android/base/GeckoScreenOrientationListener.java

@@ -11,15 +11,9 @@ import android.view.OrientationEventListener;
 import android.view.Surface;
 
 import java.util.Arrays;
-import java.util.ArrayList;
 import java.util.List;
 
-import org.json.JSONArray;
+public class GeckoScreenOrientationListener {
-import org.json.JSONObject;
-
-import org.mozilla.gecko.util.GeckoEventListener;
-
-public class GeckoScreenOrientationListener implements GeckoEventListener {
     private static final String LOGTAG = "GeckoScreenOrientationListener";
 
     static class OrientationEventListenerImpl extends OrientationEventListener {
@@ -61,12 +55,12 @@ public class GeckoScreenOrientationListener implements GeckoEventListener {
     private GeckoScreenOrientationListener() {
         mListener = new OrientationEventListenerImpl(GeckoApp.mAppContext);
 
-        ArrayList<String> prefs = new ArrayList<String>();
+        PrefsHelper.getPref(DEFAULT_ORIENTATION_PREF, new PrefsHelper.PrefHandlerBase() {
-        prefs.add(DEFAULT_ORIENTATION_PREF);
+            @Override public void prefValue(String pref, String value) {
-        JSONArray jsonPrefs = new JSONArray(prefs);
+                mDefaultOrientation = orientationFromStringArray(value);
-        GeckoAppShell.registerEventListener("Preferences:Data", this);
+                unlockScreenOrientation();
-        GeckoEvent event = GeckoEvent.createBroadcastEvent("Preferences:Get", jsonPrefs.toString());
+            }
-        GeckoAppShell.sendEventToGecko(event);
+        });
 
         mDefaultOrientation = DEFAULT_ORIENTATION;
     }
@@ -121,30 +115,6 @@ public class GeckoScreenOrientationListener implements GeckoEventListener {
         mListener.disable();
     }
 
-    public void handleMessage(String event, JSONObject message) {
-        try {
-            if ("Preferences:Data".equals(event)) {
-                JSONArray jsonPrefs = message.getJSONArray("preferences");
-                final int length = jsonPrefs.length();
-                for (int i = 0; i < length; i++) {
-                    JSONObject jPref = jsonPrefs.getJSONObject(i);
-                    final String prefName = jPref.getString("name");
-
-                    if (DEFAULT_ORIENTATION_PREF.equals(prefName)) {
-                        final String value = jPref.getString("value");
-                        mDefaultOrientation = orientationFromStringArray(value);
-                        unlockScreenOrientation();
-
-                        // this is the only pref we care about. unregister after we receive it
-                        GeckoAppShell.unregisterEventListener("Preferences:Data", this);
-                    }
-                }
-            }
-        } catch (Exception e) {
-            Log.e(LOGTAG, "Exception handling message \"" + event + "\":", e);
-        }
-    }
-
     private short orientationFromStringArray(String val) {
         List<String> orientations = Arrays.asList(val.split(","));
         // if nothing is listed, return unspecified

mobile/android/base/Makefile.in

@@ -96,6 +96,7 @@ FENNEC_JAVA_FILES = \
   NSSBridge.java \
   CustomEditText.java \
   OnInterceptTouchListener.java \
+  PrefsHelper.java \
   PrivateDataPreference.java \
   PropertyAnimator.java \
   ProfileMigrator.java \

mobile/android/base/PrefsHelper.java

@@ -0,0 +1,168 @@
+/* -*- Mode: Java; c-basic-offset: 4; tab-width: 20; indent-tabs-mode: nil; -*-
+ * This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
+
+package org.mozilla.gecko;
+
+import org.mozilla.gecko.util.GeckoEventListener;
+
+import org.json.JSONArray;
+import org.json.JSONException;
+import org.json.JSONObject;
+
+import android.util.Log;
+
+import java.util.HashMap;
+import java.util.Map;
+
+/**
+ * Helper class to get/set gecko prefs.
+ */
+public final class PrefsHelper {
+    private static final String LOGTAG = "GeckoPrefsHelper";
+
+    private static boolean sRegistered = false;
+    private static final Map<Integer, PrefHandler> sCallbacks = new HashMap<Integer, PrefHandler>();
+    private static int sUniqueRequestId = 1;
+
+    public static void getPref(String prefName, PrefHandler callback) {
+        JSONArray prefs = new JSONArray();
+        prefs.put(prefName);
+        getPrefs(prefs, callback);
+    }
+
+    public static void getPrefs(String[] prefNames, PrefHandler callback) {
+        JSONArray prefs = new JSONArray();
+        for (String p : prefNames) {
+            prefs.put(p);
+        }
+        getPrefs(prefs, callback);
+    }
+
+    public static void getPrefs(JSONArray prefNames, PrefHandler callback) {
+        int requestId;
+        synchronized (PrefsHelper.class) {
+            ensureRegistered();
+
+            requestId = sUniqueRequestId++;
+            sCallbacks.put(requestId, callback);
+        }
+
+        GeckoEvent event;
+        try {
+            JSONObject message = new JSONObject();
+            message.put("requestId", requestId);
+            message.put("preferences", prefNames);
+            event = GeckoEvent.createBroadcastEvent("Preferences:Get", message.toString());
+            GeckoAppShell.sendEventToGecko(event);
+        } catch (Exception e) {
+            Log.e(LOGTAG, "Error while composing Preferences:Get message", e);
+
+            // if we failed to send the message, drop our reference to the callback because
+            // otherwise it will leak since we will never get the response
+            synchronized (PrefsHelper.class) {
+                sCallbacks.remove(requestId);
+            }
+        }
+    }
+
+    private static void ensureRegistered() {
+        if (sRegistered) {
+            return;
+        }
+
+        GeckoAppShell.getEventDispatcher().registerEventListener("Preferences:Data", new GeckoEventListener() {
+            @Override public void handleMessage(String event, JSONObject message) {
+                try {
+                    PrefHandler callback;
+                    synchronized (PrefsHelper.class) {
+                        try {
+                            callback = sCallbacks.remove(message.getInt("requestId"));
+                        } catch (Exception e) {
+                            callback = null;
+                        }
+                    }
+                    if (callback == null) {
+                        Log.d(LOGTAG, "Preferences:Data message had an unknown requestId; ignoring");
+                        return;
+                    }
+
+                    JSONArray jsonPrefs = message.getJSONArray("preferences");
+                    for (int i = 0; i < jsonPrefs.length(); i++) {
+                        JSONObject pref = jsonPrefs.getJSONObject(i);
+                        String name = pref.getString("name");
+                        String type = pref.getString("type");
+                        try {
+                            if ("bool".equals(type)) {
+                                callback.prefValue(name, pref.getBoolean("value"));
+                            } else if ("int".equals(type)) {
+                                callback.prefValue(name, pref.getInt("value"));
+                            } else if ("string".equals(type)) {
+                                callback.prefValue(name, pref.getString("value"));
+                            } else {
+                                Log.e(LOGTAG, "Unknown pref value type [" + type + "] for pref [" + name + "]");
+                            }
+                        } catch (Exception e) {
+                            Log.e(LOGTAG, "Handler for preference [" + name + "] threw exception", e);
+                        }
+                    }
+                    callback.finish();
+                } catch (Exception e) {
+                    Log.e(LOGTAG, "Error handling Preferences:Data message", e);
+                }
+            }
+        });
+        sRegistered = true;
+    }
+
+    public static void setPref(String pref, Object value) {
+        if (pref == null || pref.length() == 0) {
+            throw new IllegalArgumentException("Pref name must be non-empty");
+        }
+
+        try {
+            JSONObject jsonPref = new JSONObject();
+            jsonPref.put("name", pref);
+            if (value instanceof Boolean) {
+                jsonPref.put("type", "bool");
+                jsonPref.put("value", ((Boolean)value).booleanValue());
+            } else if (value instanceof Integer) {
+                jsonPref.put("type", "int");
+                jsonPref.put("value", ((Integer)value).intValue());
+            } else {
+                jsonPref.put("type", "string");
+                jsonPref.put("value", String.valueOf(value));
+            }
+
+            GeckoEvent event = GeckoEvent.createBroadcastEvent("Preferences:Set", jsonPref.toString());
+            GeckoAppShell.sendEventToGecko(event);
+        } catch (JSONException e) {
+            Log.e(LOGTAG, "Error setting pref [" + pref + "]", e);
+        }
+    }
+
+    public interface PrefHandler {
+        void prefValue(String pref, boolean value);
+        void prefValue(String pref, int value);
+        void prefValue(String pref, String value);
+        void finish();
+    }
+
+    public static abstract class PrefHandlerBase implements PrefHandler {
+        public void prefValue(String pref, boolean value) {
+            Log.w(LOGTAG, "Unhandled boolean value for pref [" + pref + "]");
+        }
+
+        public void prefValue(String pref, int value) {
+            Log.w(LOGTAG, "Unhandled int value for pref [" + pref + "]");
+        }
+
+        public void prefValue(String pref, String value) {
+            Log.w(LOGTAG, "Unhandled String value for pref [" + pref + "]");
+        }
+
+        public void finish() {
+        }
+    }
+}

mobile/android/base/ProfileMigrator.java

@@ -13,11 +13,6 @@ import org.mozilla.gecko.sqlite.SQLiteBridge;
 import org.mozilla.gecko.sqlite.SQLiteBridgeException;
 import org.mozilla.gecko.sync.setup.SyncAccounts;
 import org.mozilla.gecko.sync.setup.SyncAccounts.SyncAccountParameters;
-import org.mozilla.gecko.util.GeckoEventListener;
-
-import org.json.JSONArray;
-import org.json.JSONException;
-import org.json.JSONObject;
 
 import android.accounts.Account;
 import android.content.ContentProviderOperation;
@@ -532,39 +527,26 @@ public class ProfileMigrator {
         }
     }
 
-    private class SyncTask implements Runnable, GeckoEventListener {
+    private class SyncTask implements Runnable {
-        private List<String> mSyncSettingsList;
         private Map<String, String> mSyncSettingsMap;
 
-        // Initialize preferences by sending the "Preferences:Get" command to Gecko
         protected void requestValues() {
-            mSyncSettingsList = Arrays.asList(SYNC_SETTINGS_LIST);
             mSyncSettingsMap = new HashMap<String, String>();
-            JSONArray jsonPrefs = new JSONArray(mSyncSettingsList);
+            PrefsHelper.getPrefs(SYNC_SETTINGS_LIST, new PrefsHelper.PrefHandlerBase() {
-            Log.d(LOGTAG, "Sending: " + jsonPrefs.toString());
+                @Override public void prefValue(String pref, boolean value) {
-            GeckoEvent event =
+                    mSyncSettingsMap.put(pref, value ? "1" : "0");
-                GeckoEvent.createBroadcastEvent("Preferences:Get",
-                                                jsonPrefs.toString());
-            GeckoAppShell.sendEventToGecko(event);
                 }
 
-        // Receive settings reply from Gecko, do the rest of the setup
+                @Override public void prefValue(String pref, String value) {
-        public void handleMessage(String event, JSONObject message) {
+                    if (!TextUtils.isEmpty(value)) {
-            Log.d(LOGTAG, "Received event: " + event);
+                        mSyncSettingsMap.put(pref, value);
-            try {
+                    } else {
-                if (event.equals("Preferences:Data")) {
+                        Log.w(LOGTAG, "Could not recover setting for = " + pref);
-                    // Receive most settings from Gecko's service.
+                        mSyncSettingsMap.put(pref, null);
-                    // This includes personal info, so don't log.
+                    }
-                    // Log.d(LOGTAG, "Message: " + message.toString());
+                }
-                    JSONArray jsonPrefs = message.getJSONArray("preferences");
-
-                    // Check that the batch of preferences we got notified of are in
-                    // the ones we requested and not those requested by other java code.
-                    if (!parsePrefs(jsonPrefs))
-                        return;
-
-                    unregisterEventListener("Preferences:Data", this);
 
+                @Override public void finish() {
                     // Now call the password provider to fill in the rest.
                     for (String location: SYNC_REALM_LIST) {
                         Log.d(LOGTAG, "Checking: " + location);
@@ -581,9 +563,7 @@ public class ProfileMigrator {
                     // Call Sync and transfer settings.
                     configureSync();
                 }
-            } catch (Exception e) {
+            });
-                Log.e(LOGTAG, "Exception handling message \"" + event + "\":", e);
-            }
         }
 
         protected String getPassword(String realm) {
@@ -619,41 +599,6 @@ public class ProfileMigrator {
             return result;
         }
 
-        // Returns true if we sucessfully got the preferences we requested.
-        protected boolean parsePrefs(JSONArray jsonPrefs) {
-            try {
-                final int length = jsonPrefs.length();
-                for (int i = 0; i < length; i++) {
-                    JSONObject jPref = jsonPrefs.getJSONObject(i);
-                    final String prefName = jPref.getString("name");
-
-                    // Check to make sure we're working with preferences we requested.
-                    if (!mSyncSettingsList.contains(prefName))
-                        return false;
-
-                    final String prefType = jPref.getString("type");
-                    if ("bool".equals(prefType)) {
-                        final boolean value = jPref.getBoolean("value");
-                        mSyncSettingsMap.put(prefName, value ? "1" : "0");
-                    } else {
-                        final String value = jPref.getString("value");
-                        if (!TextUtils.isEmpty(value)) {
-                            mSyncSettingsMap.put(prefName, value);
-                        } else {
-                            Log.w(LOGTAG, "Could not recover setting for = " + prefName);
-                            mSyncSettingsMap.put(prefName, null);
-                        }
-                    }
-                }
-            } catch (JSONException e) {
-                Log.e(LOGTAG, "Exception handling preferences answer: "
-                      + e.getMessage());
-                return false;
-            }
-
-            return true;
-        }
-
         protected void configureSync() {
             final String userName = mSyncSettingsMap.get("services.sync.account");
             final String syncKey = mSyncSettingsMap.get("Mozilla Services Encryption Passphrase");
@@ -692,7 +637,6 @@ public class ProfileMigrator {
         protected void registerAndRequest() {
             GeckoAppShell.getHandler().post(new Runnable() {
                 public void run() {
-                    registerEventListener("Preferences:Data", SyncTask.this);
                     requestValues();
                 }
             });
@@ -718,14 +662,6 @@ public class ProfileMigrator {
                 }
             }.execute(mContext);
         }
-
-        private void registerEventListener(String event, GeckoEventListener listener) {
-            GeckoAppShell.getEventDispatcher().registerEventListener(event, listener);
-        }
-
-        private void unregisterEventListener(String event, GeckoEventListener listener) {
-            GeckoAppShell.getEventDispatcher().unregisterEventListener(event, listener);
-        }
     }
 
     private class MiscTask implements Runnable {

mobile/android/base/gfx/DisplayPortCalculator.java

@@ -6,6 +6,7 @@
 package org.mozilla.gecko.gfx;
 
 import org.mozilla.gecko.GeckoAppShell;
+import org.mozilla.gecko.PrefsHelper;
 import org.mozilla.gecko.util.FloatUtils;
 
 import org.json.JSONArray;
@@ -15,6 +16,7 @@ import android.graphics.RectF;
 import android.util.FloatMath;
 import android.util.Log;
 
+import java.util.HashMap;
 import java.util.Map;
 
 final class DisplayPortCalculator {
@@ -58,7 +60,8 @@ final class DisplayPortCalculator {
         sStrategy.resetPageState();
     }
 
-    static void addPrefNames(JSONArray prefs) {
+    static void initPrefs() {
+        JSONArray prefs = new JSONArray();
         prefs.put(PREF_DISPLAYPORT_STRATEGY);
         prefs.put(PREF_DISPLAYPORT_FM_MULTIPLIER);
         prefs.put(PREF_DISPLAYPORT_FM_DANGER_X);
@@ -71,6 +74,18 @@ final class DisplayPortCalculator {
         prefs.put(PREF_DISPLAYPORT_VB_DANGER_X_INCR);
         prefs.put(PREF_DISPLAYPORT_VB_DANGER_Y_INCR);
         prefs.put(PREF_DISPLAYPORT_PB_VELOCITY_THRESHOLD);
+
+        PrefsHelper.getPrefs(prefs, new PrefsHelper.PrefHandlerBase() {
+            private Map<String, Integer> mValues = new HashMap<String, Integer>();
+
+            @Override public void prefValue(String pref, int value) {
+                mValues.put(pref, value);
+            }
+
+            @Override public void finish() {
+                setStrategy(mValues);
+            }
+        });
     }
 
     /**

mobile/android/base/gfx/GeckoLayerClient.java

@@ -15,7 +15,6 @@ import org.mozilla.gecko.ui.PanZoomTarget;
 import org.mozilla.gecko.util.EventDispatcher;
 import org.mozilla.gecko.util.GeckoEventResponder;
 
-import org.json.JSONArray;
 import org.json.JSONException;
 import org.json.JSONObject;
 
@@ -130,17 +129,14 @@ public class GeckoLayerClient
         registerEventListener("Viewport:PageSize");
         registerEventListener("Viewport:CalculateDisplayPort");
         registerEventListener("Checkerboard:Toggle");
-        registerEventListener("Preferences:Data");
 
         mView.setListener(this);
         mView.setLayerRenderer(mLayerRenderer);
 
         sendResizeEventIfNecessary(true);
 
-        JSONArray prefs = new JSONArray();
+        DisplayPortCalculator.initPrefs();
-        DisplayPortCalculator.addPrefNames(prefs);
+        PluginLayer.initPrefs();
-        PluginLayer.addPrefNames(prefs);
-        GeckoAppShell.sendEventToGecko(GeckoEvent.createBroadcastEvent("Preferences:Get", prefs.toString()));
     }
 
     public void destroy() {
@@ -149,7 +145,6 @@ public class GeckoLayerClient
         unregisterEventListener("Viewport:PageSize");
         unregisterEventListener("Viewport:CalculateDisplayPort");
         unregisterEventListener("Checkerboard:Toggle");
-        unregisterEventListener("Preferences:Data");
     }
 
     private void registerEventListener(String event) {
@@ -362,25 +357,6 @@ public class GeckoLayerClient
                 mReturnDisplayPort = DisplayPortCalculator.calculate(newMetrics, null);
             } else if ("Checkerboard:Toggle".equals(event)) {
                 mView.setCheckerboardShouldShowChecks(message.getBoolean("value"));
-            } else if ("Preferences:Data".equals(event)) {
-                JSONArray jsonPrefs = message.getJSONArray("preferences");
-                Map<String, Integer> prefValues = new HashMap<String, Integer>();
-                for (int i = jsonPrefs.length() - 1; i >= 0; i--) {
-                    JSONObject pref = jsonPrefs.getJSONObject(i);
-                    String name = pref.getString("name");
-                    try {
-                        prefValues.put(name, pref.getInt("value"));
-                    } catch (JSONException je) {
-                        // the pref value couldn't be parsed as an int. drop this pref
-                        // and continue with the rest
-                    }
-                }
-                // check return value from setStrategy to make sure that this is the
-                // right batch of prefs, since other java code may also have sent requests
-                // for prefs.
-                if (DisplayPortCalculator.setStrategy(prefValues) && PluginLayer.setUsePlaceholder(prefValues)) {
-                    unregisterEventListener("Preferences:Data");
-                }
             }
         } catch (JSONException e) {
             Log.e(LOGTAG, "Error decoding JSON in " + event + " handler", e);

mobile/android/base/gfx/PluginLayer.java

@@ -6,11 +6,10 @@ package org.mozilla.gecko.gfx;
 
 import org.mozilla.gecko.GeckoApp;
 import org.mozilla.gecko.GeckoAppShell;
+import org.mozilla.gecko.PrefsHelper;
 import org.mozilla.gecko.SurfaceBits;
 import org.mozilla.gecko.util.FloatUtils;
 
-import org.json.JSONArray;
-
 import android.graphics.PixelFormat;
 import android.graphics.Rect;
 import android.graphics.RectF;
@@ -22,7 +21,6 @@ import android.view.View;
 import android.widget.AbsoluteLayout;
 
 import java.nio.FloatBuffer;
-import java.util.Map;
 
 public class PluginLayer extends TileLayer {
     private static final String LOGTAG = "PluginLayer";
@@ -68,19 +66,13 @@ public class PluginLayer extends TileLayer {
         mLayoutParams = new PluginLayoutParams(rect, maxDimension);
     }
 
-    static void addPrefNames(JSONArray prefs) {
+    static void initPrefs() {
-        prefs.put(PREF_PLUGIN_USE_PLACEHOLDER);
+        PrefsHelper.getPref(PREF_PLUGIN_USE_PLACEHOLDER, new PrefsHelper.PrefHandlerBase() {
-    }
+            @Override public void prefValue(String pref, int value) {
-
+                sUsePlaceholder = (value == 1);
-    static boolean setUsePlaceholder(Map<String, Integer> prefs) {
-        Integer usePlaceholder = prefs.get(PREF_PLUGIN_USE_PLACEHOLDER);
-        if (usePlaceholder == null) {
-            return false;
-        }
-
-        sUsePlaceholder = (int)usePlaceholder == 1 ? true : false;
                 Log.i(LOGTAG, "Using plugin placeholder: " + sUsePlaceholder);
-        return true;
+            }
+        });
     }
 
     public void setVisible(boolean newVisible) {

mobile/android/base/tests/testPasswordEncrypt.java.in

@@ -129,21 +129,26 @@ public class testPasswordEncrypt extends BaseTest {
             jsonPref.put("type", "string");
             jsonPref.put("value", passwd);
             mActions.sendGeckoEvent("Preferences:Set", jsonPref.toString());
-        } catch (Exception ex) { 
-            mAsserter.ok(false, "exception in toggleMasterPassword", ex.toString());
-        }
 
             // Wait for confirmation of the pref change before proceeding with the test.
             JSONArray getPrefData = new JSONArray();
             getPrefData.put("privacy.masterpassword.enabled");
+            JSONObject message = new JSONObject();
+            message.put("requestId", "testPasswordEncrypt");
+            message.put("preferences", getPrefData);
             Actions.RepeatedEventExpecter contentEventExpecter = mActions.expectGeckoEvent("Preferences:Data");
-        mActions.sendGeckoEvent("Preferences:Get", getPrefData.toString());
+            mActions.sendGeckoEvent("Preferences:Get", message.toString());
             // Receiving a Preferences:Data event is not conclusive evidence that *our*
             // preference has been set -- another component may be changing preferences
             // at the same time. Mitigate this risk by waiting for a Preference:Data
             // and then waiting for a period of time in which no more Preference:Data
             // events are received.
+            // TODO: add a new expectGeckoEvent function that listens for a Preferences:Data
+            // message with a specific requestId
             contentEventExpecter.blockUntilClear(2000);
+        } catch (Exception ex) { 
+            mAsserter.ok(false, "exception in toggleMasterPassword", ex.toString());
+        }
     }
 
     public void tearDown() throws Exception {

mobile/android/base/ui/Axis.java

@@ -5,6 +5,7 @@
 
 package org.mozilla.gecko.ui;
 
+import org.mozilla.gecko.PrefsHelper;
 import org.mozilla.gecko.util.FloatUtils;
 
 import org.json.JSONArray;
@@ -12,6 +13,7 @@ import org.json.JSONArray;
 import android.util.Log;
 import android.view.View;
 
+import java.util.HashMap;
 import java.util.Map;
 
 /**
@@ -61,7 +63,8 @@ abstract class Axis {
         return (value == null || value < 0 ? defaultValue : value);
     }
 
-    static void addPrefNames(JSONArray prefs) {
+    static void initPrefs() {
+        JSONArray prefs = new JSONArray();
         prefs.put(PREF_SCROLLING_FRICTION_FAST);
         prefs.put(PREF_SCROLLING_FRICTION_SLOW);
         prefs.put(PREF_SCROLLING_VELOCITY_THRESHOLD);
@@ -69,6 +72,18 @@ abstract class Axis {
         prefs.put(PREF_SCROLLING_OVERSCROLL_DECEL_RATE);
         prefs.put(PREF_SCROLLING_OVERSCROLL_SNAP_LIMIT);
         prefs.put(PREF_SCROLLING_MIN_SCROLLABLE_DISTANCE);
+
+        PrefsHelper.getPrefs(prefs, new PrefsHelper.PrefHandlerBase() {
+            Map<String, Integer> mPrefs = new HashMap<String, Integer>();
+
+            @Override public void prefValue(String name, int value) {
+                mPrefs.put(name, value);
+            }
+
+            @Override public void finish() {
+                setPrefs(mPrefs);
+            }
+        });
     }
 
     static void setPrefs(Map<String, Integer> prefs) {

mobile/android/base/ui/PanZoomController.java

@@ -8,6 +8,7 @@ package org.mozilla.gecko.ui;
 import org.mozilla.gecko.GeckoApp;
 import org.mozilla.gecko.GeckoAppShell;
 import org.mozilla.gecko.GeckoEvent;
+import org.mozilla.gecko.PrefsHelper;
 import org.mozilla.gecko.ZoomConstraints;
 import org.mozilla.gecko.gfx.ImmutableViewportMetrics;
 import org.mozilla.gecko.gfx.PointUtils;
@@ -16,8 +17,6 @@ import org.mozilla.gecko.util.EventDispatcher;
 import org.mozilla.gecko.util.FloatUtils;
 import org.mozilla.gecko.util.GeckoEventListener;
 
-import org.json.JSONArray;
-import org.json.JSONException;
 import org.json.JSONObject;
 
 import android.graphics.PointF;
@@ -28,8 +27,6 @@ import android.view.GestureDetector;
 import android.view.MotionEvent;
 
 import java.util.Arrays;
-import java.util.HashMap;
-import java.util.Map;
 import java.util.StringTokenizer;
 import java.util.Timer;
 import java.util.TimerTask;
@@ -48,8 +45,6 @@ public class PanZoomController
 
     private static String MESSAGE_ZOOM_RECT = "Browser:ZoomToRect";
     private static String MESSAGE_ZOOM_PAGE = "Browser:ZoomToPageWidth";
-    private static String MESSAGE_PREFS_GET = "Preferences:Get";
-    private static String MESSAGE_PREFS_DATA = "Preferences:Data";
 
     private static final String PREF_ZOOM_ANIMATION_FRAMES = "ui.zooming.animation_frames";
 
@@ -139,18 +134,18 @@ public class PanZoomController
         mEventDispatcher = eventDispatcher;
         registerEventListener(MESSAGE_ZOOM_RECT);
         registerEventListener(MESSAGE_ZOOM_PAGE);
-        registerEventListener(MESSAGE_PREFS_DATA);
 
-        JSONArray prefs = new JSONArray();
+        PrefsHelper.getPref(PREF_ZOOM_ANIMATION_FRAMES, new PrefsHelper.PrefHandlerBase() {
-        prefs.put(PREF_ZOOM_ANIMATION_FRAMES);
+            @Override public void prefValue(String pref, String value) {
-        Axis.addPrefNames(prefs);
+                setZoomAnimationFrames(value);
-        GeckoAppShell.sendEventToGecko(GeckoEvent.createBroadcastEvent(MESSAGE_PREFS_GET, prefs.toString()));
+            }
+        });
+        Axis.initPrefs();
     }
 
     public void destroy() {
         unregisterEventListener(MESSAGE_ZOOM_RECT);
         unregisterEventListener(MESSAGE_ZOOM_PAGE);
-        unregisterEventListener(MESSAGE_PREFS_DATA);
         mSubscroller.destroy();
     }
 
@@ -213,32 +208,6 @@ public class PanZoomController
                         animatedZoomTo(r);
                     }
                 });
-            } else if (MESSAGE_PREFS_DATA.equals(event)) {
-                JSONArray jsonPrefs = message.getJSONArray("preferences");
-                Map<String, Integer> axisPrefs = new HashMap<String, Integer>();
-                String zoomAnimationFrames = null;
-                for (int i = jsonPrefs.length() - 1; i >= 0; i--) {
-                    JSONObject pref = jsonPrefs.getJSONObject(i);
-                    String name = pref.getString("name");
-                    if (PREF_ZOOM_ANIMATION_FRAMES.equals(name)) {
-                        zoomAnimationFrames = pref.getString("value");
-                    } else {
-                        try {
-                            axisPrefs.put(name, pref.getInt("value"));
-                        } catch (JSONException je) {
-                            // the value could not be parsed as an int. ignore this
-                            // pref and continue
-                        }
-                    }
-                }
-                // check for null to make sure the batch of preferences we got notified
-                // of are in the fact the ones we requested and not those requested by
-                // other java code
-                if (zoomAnimationFrames != null) {
-                    setZoomAnimationFrames(zoomAnimationFrames);
-                    Axis.setPrefs(axisPrefs);
-                    unregisterEventListener(MESSAGE_PREFS_DATA);
-                }
             }
         } catch (Exception e) {
             Log.e(LOGTAG, "Exception handling message \"" + event + "\":", e);

mobile/android/chrome/content/browser.js

@@ -811,7 +811,7 @@ var BrowserApp = {
       let json = JSON.parse(aPrefNames);
       let prefs = [];
 
-      for each (let prefName in json) {
+      for each (let prefName in json.preferences) {
         let pref = {
           name: prefName
         };
@@ -880,6 +880,7 @@ var BrowserApp = {
       sendMessageToJava({
         gecko: {
           type: "Preferences:Data",
+          requestId: json.requestId,    // opaque request identifier, can be any string/int/whatever
           preferences: prefs
         }
       });