org.apache.hadoop.hbase.client.ClientIdGenerator Maven / Gradle / Ivy
/*
* 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.io.IOException;
import java.lang.management.ManagementFactory;
import java.util.List;
import org.apache.hadoop.hbase.util.Addressing;
import org.apache.hadoop.hbase.util.Bytes;
import org.apache.hadoop.hbase.util.EnvironmentEdgeManager;
import org.apache.yetus.audience.InterfaceAudience;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;
import org.apache.hbase.thirdparty.com.google.common.base.Splitter;
import org.apache.hbase.thirdparty.com.google.common.collect.Iterators;
/**
* The class that is able to determine some unique strings for the client, such as an IP address,
* PID, and composite deterministic ID.
*/
@InterfaceAudience.Private
final class ClientIdGenerator {
private static final Logger LOG = LoggerFactory.getLogger(ClientIdGenerator.class);
private ClientIdGenerator() {
}
/**
* Returns a unique ID incorporating IP address, PID, TID and timer. Might be an overkill... Note
* though that new UUID in java by default is just a random number.
*/
public static byte[] generateClientId() {
byte[] selfBytes = getIpAddressBytes();
Long pid = getPid();
long tid = Thread.currentThread().getId();
long ts = EnvironmentEdgeManager.currentTime();
byte[] id = new byte[selfBytes.length + ((pid != null ? 1 : 0) + 2) * Bytes.SIZEOF_LONG];
int offset = Bytes.putBytes(id, 0, selfBytes, 0, selfBytes.length);
if (pid != null) {
offset = Bytes.putLong(id, offset, pid);
}
offset = Bytes.putLong(id, offset, tid);
offset = Bytes.putLong(id, offset, ts);
assert offset == id.length;
return id;
}
/** Returns PID of the current process, if it can be extracted from JVM name, or null. */
public static Long getPid() {
String name = ManagementFactory.getRuntimeMXBean().getName();
List nameParts = Splitter.on('@').splitToList(name);
if (nameParts.size() == 2) { // 12345@somewhere
try {
return Long.parseLong(Iterators.get(nameParts.iterator(), 0));
} catch (NumberFormatException ex) {
LOG.warn("Failed to get PID from [" + name + "]", ex);
}
} else {
LOG.warn("Don't know how to get PID from [" + name + "]");
}
return null;
}
/**
* Returns Some IPv4/IPv6 address available on the current machine that is up, not virtual and not
* a loopback address. Empty array if none can be found or error occurred.
*/
public static byte[] getIpAddressBytes() {
try {
return Addressing.getIpAddress().getAddress();
} catch (IOException ex) {
LOG.warn("Failed to get IP address bytes", ex);
}
return new byte[0];
}
}