| /** |
| * |
| * 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.hadoop.hbase.client; |
| |
| import java.util.Arrays; |
| import java.util.Random; |
| |
| import org.apache.hadoop.hbase.HConstants; |
| import org.apache.yetus.audience.InterfaceAudience; |
| |
| /** |
| * NonceGenerator implementation that uses client ID hash + random int as nonce group, and random |
| * numbers as nonces. |
| */ |
| @InterfaceAudience.Private |
| public final class PerClientRandomNonceGenerator implements NonceGenerator { |
| |
| private static final PerClientRandomNonceGenerator INST = new PerClientRandomNonceGenerator(); |
| |
| private final Random rdm = new Random(); |
| private final long clientId; |
| |
| private PerClientRandomNonceGenerator() { |
| byte[] clientIdBase = ClientIdGenerator.generateClientId(); |
| this.clientId = (((long) Arrays.hashCode(clientIdBase)) << 32) + rdm.nextInt(); |
| } |
| |
| @Override |
| public long getNonceGroup() { |
| return this.clientId; |
| } |
| |
| @Override |
| public long newNonce() { |
| long result = HConstants.NO_NONCE; |
| do { |
| result = rdm.nextLong(); |
| } while (result == HConstants.NO_NONCE); |
| return result; |
| } |
| |
| /** |
| * Get the singleton nonce generator. |
| */ |
| public static PerClientRandomNonceGenerator get() { |
| return INST; |
| } |
| } |