ThreadID.java

import java.lang.management.ManagementFactory;
import javax.management.MBeanServer;
import javax.management.ObjectName;

/**
 * @author vladimir.dolzhenko
 * @since 2017-01-23
 */
public class ThreadID {
    public static void main(String[] args) throws Exception {
        System.out.printf("0x%016X", getTID(Thread.currentThread().getName()));
    }

    static long getTID(String threadName) throws Exception {
        ObjectName objectName = new ObjectName("com.sun.management:type=DiagnosticCommand");
        MBeanServer mbeanServer = ManagementFactory.getPlatformMBeanServer();
        final String threadPrint = (String) mbeanServer.invoke(objectName, "threadPrint",
                                                               new Object[] {new String[] {}},
                                                               new String[] {String[].class.getName()});

        
        final String threadPrefix = '"' + threadName + "\" ";
        
        // look up for a line like:
        // "main" #1 prio=5 os_prio=0 tid=0x0000000002349000 nid=0x8ec4 waiting on condition [0x000000000255e000]

        for (String line : threadPrint.split("\n")) {
            if (line.startsWith(threadPrefix)) {
                final String tidPrefix = " tid=0x";
                final int st = line.indexOf(tidPrefix);
                if (st > 0) {
                    final int end = line.indexOf(' ', st + tidPrefix.length());
                    final String substring = line.substring(st + tidPrefix.length(), end);
                    final long tid = Long.parseLong(substring, 16);
                    return tid;
                }
            }
        }

        throw new IllegalArgumentException("no thread " + threadName);
    }
}