docs: private long cpuTime(Thread thr) {
          ThreadMXBean mxBean = ManagementFactory.getThreadMXBean();
          if (mxBean.isThreadCpuTimeSupported()) {
              try {
                  return mxBean.getThreadCpuTime(thr.getId());
              } catch (UnsupportedOperationException e) {
              }
          }
          return 0;
      }