Madan Jampani | 2546111 | 2015-02-17 14:17:29 -0800 | [diff] [blame] | 1 | /* |
| 2 | * Copyright 2015 Open Networking Laboratory |
| 3 | * |
| 4 | * Licensed under the Apache License, Version 2.0 (the "License"); |
| 5 | * you may not use this file except in compliance with the License. |
| 6 | * You may obtain a copy of the License at |
| 7 | * |
| 8 | * http://www.apache.org/licenses/LICENSE-2.0 |
| 9 | * |
| 10 | * Unless required by applicable law or agreed to in writing, software |
| 11 | * distributed under the License is distributed on an "AS IS" BASIS, |
| 12 | * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. |
| 13 | * See the License for the specific language governing permissions and |
| 14 | * limitations under the License. |
| 15 | */ |
| 16 | |
Madan Jampani | 0934270 | 2015-02-05 23:32:40 -0800 | [diff] [blame] | 17 | package org.onosproject.store.consistent.impl; |
| 18 | |
| 19 | import static com.google.common.base.Preconditions.checkState; |
| 20 | |
Madan Jampani | f1b8e17 | 2015-03-23 11:42:02 -0700 | [diff] [blame] | 21 | import java.util.List; |
Madan Jampani | 0934270 | 2015-02-05 23:32:40 -0800 | [diff] [blame] | 22 | import com.google.common.base.Charsets; |
Madan Jampani | f1b8e17 | 2015-03-23 11:42:02 -0700 | [diff] [blame] | 23 | import com.google.common.collect.ImmutableList; |
Madan Jampani | 0934270 | 2015-02-05 23:32:40 -0800 | [diff] [blame] | 24 | import com.google.common.hash.Hashing; |
| 25 | |
| 26 | /** |
Madan Jampani | 7804c99 | 2015-07-20 13:20:19 -0700 | [diff] [blame] | 27 | * Partitioner for mapping map entries to individual database partitions. |
Madan Jampani | 0934270 | 2015-02-05 23:32:40 -0800 | [diff] [blame] | 28 | * <p> |
Madan Jampani | 7804c99 | 2015-07-20 13:20:19 -0700 | [diff] [blame] | 29 | * By default a md5 hash of the hash key (key or map name) is used to pick a |
Madan Jampani | 0934270 | 2015-02-05 23:32:40 -0800 | [diff] [blame] | 30 | * partition. |
| 31 | */ |
| 32 | public abstract class DatabasePartitioner implements Partitioner<String> { |
| 33 | // Database partitions sorted by their partition name. |
Madan Jampani | f1b8e17 | 2015-03-23 11:42:02 -0700 | [diff] [blame] | 34 | protected final List<Database> partitions; |
Madan Jampani | 0934270 | 2015-02-05 23:32:40 -0800 | [diff] [blame] | 35 | |
Madan Jampani | f1b8e17 | 2015-03-23 11:42:02 -0700 | [diff] [blame] | 36 | public DatabasePartitioner(List<Database> partitions) { |
| 37 | checkState(partitions != null && !partitions.isEmpty(), "Partitions cannot be null or empty"); |
| 38 | this.partitions = ImmutableList.copyOf(partitions); |
Madan Jampani | 0934270 | 2015-02-05 23:32:40 -0800 | [diff] [blame] | 39 | } |
| 40 | |
| 41 | protected int hash(String key) { |
| 42 | return Math.abs(Hashing.md5().newHasher().putBytes(key.getBytes(Charsets.UTF_8)).hash().asInt()); |
| 43 | } |
| 44 | |
| 45 | } |