Topics can now have an Importance.

Bug: 22451710
Change-Id: I627121da6c4b85492715a8e8a099656dca52b734
diff --git a/services/core/java/com/android/server/notification/TopicImportanceExtractor.java b/services/core/java/com/android/server/notification/TopicImportanceExtractor.java
new file mode 100644
index 0000000..01770d0
--- /dev/null
+++ b/services/core/java/com/android/server/notification/TopicImportanceExtractor.java
@@ -0,0 +1,56 @@
+/**
+* Copyright (C) 2015 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.server.notification;
+
+import android.content.Context;
+import android.util.Slog;
+
+/**
+ * Determines the importance of the given notification.
+ */
+public class TopicImportanceExtractor implements NotificationSignalExtractor {
+    private static final String TAG = "ImportantTopicExtractor";
+    private static final boolean DBG = false;
+
+    private RankingConfig mConfig;
+
+    public void initialize(Context ctx, NotificationUsageStats usageStats) {
+        if (DBG) Slog.d(TAG, "Initializing  " + getClass().getSimpleName() + ".");
+    }
+
+    public RankingReconsideration process(NotificationRecord record) {
+        if (record == null || record.getNotification() == null) {
+            if (DBG) Slog.d(TAG, "skipping empty notification");
+            return null;
+        }
+
+        if (mConfig == null) {
+            if (DBG) Slog.d(TAG, "missing config");
+            return null;
+        }
+
+        final int topicImportance = mConfig.getTopicImportance(record.sbn.getPackageName(),
+                record.sbn.getUid(), record.sbn.getNotification().getTopic());
+        record.setTopicImportance(topicImportance);
+
+        return null;
+    }
+
+    @Override
+    public void setConfig(RankingConfig config) {
+        mConfig = config;
+    }
+}