com.metamx.metrics.JvmPidDiscoverer Maven / Gradle / Ivy
/*
* Copyright 2017 Metamarkets Group Inc.
*
* 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.
*/
package com.metamx.metrics;
import com.metamx.common.RE;
import java.lang.management.ManagementFactory;
import java.util.regex.Pattern;
/**
* For systems that for whatever reason cannot use Sigar (through com.metamx.metrics.SigarPidDiscoverer ),
* this attempts to get the PID from the JVM "name".
*/
public class JvmPidDiscoverer implements PidDiscoverer
{
private static final JvmPidDiscoverer INSTANCE = new JvmPidDiscoverer();
public static JvmPidDiscoverer instance()
{
return INSTANCE;
}
/**
* use {JvmPidDiscoverer.instance()}
*/
private JvmPidDiscoverer()
{
}
/**
* Returns the PID as a best guess. This uses methods that are not guaranteed to actually be the PID.
*
* TODO: switch to ProcessHandle.current().getPid() for java9 potentially
*
* @return the PID of the current jvm if available
*
* @throws RuntimeException if the pid cannot be determined
*/
@Override
public long getPid()
{
return Inner.PID;
}
private static class Inner
{
private static final long PID;
static {
final String jvmName = ManagementFactory.getRuntimeMXBean().getName();
final String[] nameSplits = jvmName.split(Pattern.quote("@"));
if (nameSplits.length != 2) {
throw new RE("Unable to determine pid from [%s]", jvmName);
}
try {
PID = Long.parseLong(nameSplits[0]);
}
catch (NumberFormatException nfe) {
throw new RE(nfe, "Unable to determine pid from [%s]", jvmName);
}
}
}
}