Github user eribeiro commented on a diff in the pull request:
https://github.com/apache/zookeeper/pull/632#discussion_r225016509
--- Diff:
zookeeper-server/src/main/java/org/apache/zookeeper/server/util/AdHash.java ---
@@ -0,0 +1,84 @@
+/**
+ * Licensed to the Apache Software Foundation (ASF) under one
+ * or more contributor license agreements. See the NOTICE file
+ * distributed with this work for additional information
+ * regarding copyright ownership. The ASF licenses this file
+ * to you 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 org.apache.zookeeper.server.util;
+
+/**
+ * This incremental hash is used to keep track of the hash of
+ * the data tree to that we can quickly validate that things
+ * are in sync.
+ *
+ * See the excellent paper: A New Paradigm for collision-free hashing:
+ * Incrementality at reduced cost, M. Bellare and D. Micciancio
+ */
+public class AdHash {
--- End diff --
Sometimes it is better to make it less restrictive and loosen up afterwards
than make it more open and not being able to close thereafter. ;) But sure, it
can go without this restriction.
---
