Bug 1244071 - Move reading of restrictions to dedicated cache class. r=mcomella

MozReview-Commit-ID: 7u40m0Wdusi

--HG--
extra : rebase_source : 135c9af9820277f7b910722510fe6a470300f31b
extra : amend_source : 4ab9ee588b09cce10b29d851e9915ac8a35f1a38

mobile/android/base/java/org/mozilla/gecko/Restrictions.java

@@ -5,21 +5,21 @@
 
 package org.mozilla.gecko;
 
+import android.annotation.TargetApi;
+import android.content.Context;
+import android.os.Build;
+import android.util.Log;
+
+import org.mozilla.gecko.AppConstants.Versions;
 import org.mozilla.gecko.annotation.RobocopTarget;
 import org.mozilla.gecko.annotation.WrapForJNI;
-import org.mozilla.gecko.AppConstants.Versions;
 import org.mozilla.gecko.restrictions.DefaultConfiguration;
 import org.mozilla.gecko.restrictions.GuestProfileConfiguration;
 import org.mozilla.gecko.restrictions.Restrictable;
 import org.mozilla.gecko.restrictions.RestrictedProfileConfiguration;
+import org.mozilla.gecko.restrictions.RestrictionCache;
 import org.mozilla.gecko.restrictions.RestrictionConfiguration;
 
-import android.annotation.TargetApi;
-import android.content.Context;
-import android.os.Build;
-import android.os.UserManager;
-import android.util.Log;
-
 @RobocopTarget
 public class Restrictions {
     private static final String LOGTAG = "GeckoRestrictedProfiles";
@@ -74,8 +74,7 @@ public class Restrictions {
         }
 
         // The user is on a restricted profile if, and only if, we injected application restrictions during account setup.
-        final UserManager mgr = (UserManager) context.getSystemService(Context.USER_SERVICE);
+        return RestrictionCache.hasApplicationRestrictions(context);
-        return !mgr.getApplicationRestrictions(context.getPackageName()).isEmpty();
     }
 
     public static void update(Context context) {

mobile/android/base/java/org/mozilla/gecko/restrictions/RestrictedProfileConfiguration.java

@@ -66,9 +66,6 @@ public class RestrictedProfileConfiguration implements RestrictionConfiguration
     }
 
     private Context context;
-    private Bundle cachedAppRestrictions;
-    private Bundle cachedUserRestrictions;
-    private boolean isCacheInvalid = true;
 
     public RestrictedProfileConfiguration(Context context) {
         this.context = context.getApplicationContext();
@@ -76,38 +73,17 @@ public class RestrictedProfileConfiguration implements RestrictionConfiguration
 
     @Override
     public synchronized boolean isAllowed(Restrictable restrictable) {
-        if (isCacheInvalid || !ThreadUtils.isOnUiThread()) {
-            readRestrictions();
-            isCacheInvalid = false;
-        }
-
         // Special casing system/user restrictions
         if (restrictable == Restrictable.INSTALL_APPS || restrictable == Restrictable.MODIFY_ACCOUNTS) {
-            return !cachedUserRestrictions.getBoolean(restrictable.name);
+            return RestrictionCache.getUserRestriction(context, restrictable.name);
         }
 
-        if (!cachedAppRestrictions.containsKey(restrictable.name) && !configuration.containsKey(restrictable)) {
+        if (!RestrictionCache.hasApplicationRestriction(context, restrictable.name) && !configuration.containsKey(restrictable)) {
             // Always allow features that are not in the configuration
             return true;
         }
 
-        return cachedAppRestrictions.getBoolean(restrictable.name, configuration.get(restrictable));
+        return RestrictionCache.getApplicationRestriction(context, restrictable.name, configuration.get(restrictable));
-    }
-
-    private void readRestrictions() {
-        final UserManager mgr = (UserManager) context.getSystemService(Context.USER_SERVICE);
-
-        StrictMode.ThreadPolicy policy = StrictMode.allowThreadDiskReads();
-
-        try {
-            Bundle appRestrictions = mgr.getApplicationRestrictions(context.getPackageName());
-            migrateRestrictionsIfNeeded(appRestrictions);
-
-            cachedAppRestrictions = appRestrictions;
-            cachedUserRestrictions = mgr.getUserRestrictions();
-        } finally {
-            StrictMode.setThreadPolicy(policy);
-        }
     }
 
     @Override
@@ -135,7 +111,7 @@ public class RestrictedProfileConfiguration implements RestrictionConfiguration
 
     @Override
     public synchronized void update() {
-        isCacheInvalid = true;
+        RestrictionCache.invalidate();
     }
 
     public static List<Restrictable> getVisibleRestrictions() {
@@ -150,25 +126,4 @@ public class RestrictedProfileConfiguration implements RestrictionConfiguration
 
         return visibleList;
     }
-
-    /**
-     * This method migrates the old set of DISALLOW_ restrictions to the new restrictable feature ones (Bug 1189336).
-     */
-    public static void migrateRestrictionsIfNeeded(Bundle bundle) {
-        if (!bundle.containsKey(Restrictable.INSTALL_EXTENSION.name) && bundle.containsKey("no_install_extensions")) {
-            bundle.putBoolean(Restrictable.INSTALL_EXTENSION.name, !bundle.getBoolean("no_install_extensions"));
-        }
-
-        if (!bundle.containsKey(Restrictable.PRIVATE_BROWSING.name) && bundle.containsKey("no_private_browsing")) {
-            bundle.putBoolean(Restrictable.PRIVATE_BROWSING.name, !bundle.getBoolean("no_private_browsing"));
-        }
-
-        if (!bundle.containsKey(Restrictable.CLEAR_HISTORY.name) && bundle.containsKey("no_clear_history")) {
-            bundle.putBoolean(Restrictable.CLEAR_HISTORY.name, !bundle.getBoolean("no_clear_history"));
-        }
-
-        if (!bundle.containsKey(Restrictable.ADVANCED_SETTINGS.name) && bundle.containsKey("no_advanced_settings")) {
-            bundle.putBoolean(Restrictable.ADVANCED_SETTINGS.name, !bundle.getBoolean("no_advanced_settings"));
-        }
-    }
 }

mobile/android/base/java/org/mozilla/gecko/restrictions/RestrictionCache.java

@@ -0,0 +1,99 @@
+/* -*- Mode: Java; c-basic-offset: 4; tab-width: 4; 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.restrictions;
+
+import android.annotation.TargetApi;
+import android.content.Context;
+import android.os.Build;
+import android.os.Bundle;
+import android.os.StrictMode;
+import android.os.UserManager;
+
+import org.mozilla.gecko.util.ThreadUtils;
+
+/**
+ * Cache for user and application restrictions.
+ */
+public class RestrictionCache {
+    private static Bundle cachedAppRestrictions;
+    private static Bundle cachedUserRestrictions;
+    private static boolean isCacheInvalid = true;
+
+    private RestrictionCache() {}
+
+    public static synchronized boolean getUserRestriction(Context context, String restriction) {
+        updateCacheIfNeeded(context);
+        return cachedUserRestrictions.getBoolean(restriction);
+    }
+
+    public static synchronized boolean hasApplicationRestriction(Context context, String restriction) {
+        updateCacheIfNeeded(context);
+        return cachedAppRestrictions.containsKey(restriction);
+    }
+
+    public static synchronized boolean getApplicationRestriction(Context context, String restriction, boolean defaultValue) {
+        updateCacheIfNeeded(context);
+        return cachedAppRestrictions.getBoolean(restriction, defaultValue);
+    }
+
+    public static synchronized boolean hasApplicationRestrictions(Context context) {
+        updateCacheIfNeeded(context);
+        return !cachedAppRestrictions.isEmpty();
+    }
+
+    public static synchronized void invalidate() {
+        isCacheInvalid = true;
+    }
+
+    private static void updateCacheIfNeeded(Context context) {
+        // If we are not on the UI thread then we can just go ahead and read the values (Bug 1189347).
+        // Otherwise we read from the cache to avoid blocking the UI thread. If the cache is invalid
+        // then we hazard the consequences and just do the read.
+        if (isCacheInvalid || !ThreadUtils.isOnUiThread()) {
+            readRestrictions(context);
+            isCacheInvalid = false;
+        }
+    }
+
+    @TargetApi(Build.VERSION_CODES.JELLY_BEAN_MR2)
+    private static void readRestrictions(Context context) {
+        final UserManager mgr = (UserManager) context.getSystemService(Context.USER_SERVICE);
+
+        // If we do not have anything in the cache yet then this read might happen on the UI thread (Bug 1189347).
+        final StrictMode.ThreadPolicy policy = StrictMode.allowThreadDiskReads();
+
+        try {
+            Bundle appRestrictions = mgr.getApplicationRestrictions(context.getPackageName());
+            migrateRestrictionsIfNeeded(appRestrictions);
+
+            cachedAppRestrictions = appRestrictions;
+            cachedUserRestrictions = mgr.getUserRestrictions(); // Always implies disk read
+        } finally {
+            StrictMode.setThreadPolicy(policy);
+        }
+    }
+
+    /**
+     * This method migrates the old set of DISALLOW_ restrictions to the new restrictable feature ones (Bug 1189336).
+     */
+    /* package-private */ static void migrateRestrictionsIfNeeded(Bundle bundle) {
+        if (!bundle.containsKey(Restrictable.INSTALL_EXTENSION.name) && bundle.containsKey("no_install_extensions")) {
+            bundle.putBoolean(Restrictable.INSTALL_EXTENSION.name, !bundle.getBoolean("no_install_extensions"));
+        }
+
+        if (!bundle.containsKey(Restrictable.PRIVATE_BROWSING.name) && bundle.containsKey("no_private_browsing")) {
+            bundle.putBoolean(Restrictable.PRIVATE_BROWSING.name, !bundle.getBoolean("no_private_browsing"));
+        }
+
+        if (!bundle.containsKey(Restrictable.CLEAR_HISTORY.name) && bundle.containsKey("no_clear_history")) {
+            bundle.putBoolean(Restrictable.CLEAR_HISTORY.name, !bundle.getBoolean("no_clear_history"));
+        }
+
+        if (!bundle.containsKey(Restrictable.ADVANCED_SETTINGS.name) && bundle.containsKey("no_advanced_settings")) {
+            bundle.putBoolean(Restrictable.ADVANCED_SETTINGS.name, !bundle.getBoolean("no_advanced_settings"));
+        }
+    }
+}

mobile/android/base/java/org/mozilla/gecko/restrictions/RestrictionProvider.java

@@ -38,7 +38,7 @@ public class RestrictionProvider extends BroadcastReceiver {
             @Override
             public void run() {
                 final Bundle oldRestrictions = intent.getBundleExtra(Intent.EXTRA_RESTRICTIONS_BUNDLE);
-                RestrictedProfileConfiguration.migrateRestrictionsIfNeeded(oldRestrictions);
+                RestrictionCache.migrateRestrictionsIfNeeded(oldRestrictions);
 
                 final Bundle extras = new Bundle();
 

mobile/android/base/moz.build

@@ -505,6 +505,7 @@ gbjar.sources += ['java/org/mozilla/gecko/' + x for x in [
     'restrictions/GuestProfileConfiguration.java',
     'restrictions/Restrictable.java',
     'restrictions/RestrictedProfileConfiguration.java',
+    'restrictions/RestrictionCache.java',
     'restrictions/RestrictionConfiguration.java',
     'restrictions/RestrictionProvider.java',
     'ScreenshotObserver.java',