/
OAutoShardingMurmurStrategy.java
executable file
·45 lines (40 loc) · 1.62 KB
/
OAutoShardingMurmurStrategy.java
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
/*
*
* * Copyright 2014 Orient Technologies LTD (info(at)orientechnologies.com)
* *
* * 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.
* *
* * For more information: http://www.orientechnologies.com
*
*/
package com.orientechnologies.orient.core.sharding.auto;
import com.orientechnologies.common.serialization.types.OBinarySerializer;
import com.orientechnologies.orient.core.index.hashindex.local.OMurmurHash3HashFunction;
import static java.lang.Math.abs;
/**
* Auto-sharding strategy implementation that uses Murmur hashing.
*
* @since 3.0
* @author Luca Garulli
*/
public final class OAutoShardingMurmurStrategy implements OAutoShardingStrategy {
private OMurmurHash3HashFunction hashFunction = new OMurmurHash3HashFunction<Object>();
public OAutoShardingMurmurStrategy(final OBinarySerializer keySerializer) {
hashFunction.setValueSerializer(keySerializer);
}
public int getPartitionsId(final Object iKey, final int partitionSize) {
long hash = hashFunction.hashCode(iKey);
hash = hash == Long.MIN_VALUE ? 0 : abs(hash);
return (int) (hash % partitionSize);
}
}