NoMan: Fix inconsistent notification comparator
Switch second phase of notification sorting to lexicographic
string comparison in order to enforce a consistent comparison.
Note that this slightly changes the logic: Within groups we
previously fell back on authoritative rank comparison when
one of the notificiations didn't have a sort key. Now we
just replace missing sort keys with " ".
Bug: 16626175
Change-Id: I91f4f4afeeb2c8edda6cd2668011a7367795086c
diff --git a/services/core/java/com/android/server/notification/GlobalSortKeyComparator.java b/services/core/java/com/android/server/notification/GlobalSortKeyComparator.java
new file mode 100644
index 0000000..ce976d2
--- /dev/null
+++ b/services/core/java/com/android/server/notification/GlobalSortKeyComparator.java
@@ -0,0 +1,34 @@
+/*
+ * Copyright (C) 2014 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 java.util.Comparator;
+
+/**
+ * Sorts notifications by their global sort key.
+ */
+public class GlobalSortKeyComparator implements Comparator<NotificationRecord> {
+ @Override
+ public int compare(NotificationRecord left, NotificationRecord right) {
+ if (left.getGlobalSortKey() == null) {
+ throw new IllegalStateException("Missing left global sort key: " + left);
+ }
+ if (right.getGlobalSortKey() == null) {
+ throw new IllegalStateException("Missing right global sort key: " + right);
+ }
+ return left.getGlobalSortKey().compareTo(right.getGlobalSortKey());
+ }
+}