@Override
  public long getPid() {
    final JMXServiceURL url;
    try {
      url =
          new JMXServiceURL(
              String.format("service:jmx:rmi:///jndi/rmi://127.0.0.1:%d/jmxrmi", jmxPort));
    } catch (final MalformedURLException ignored) {
      return -1;
    }
    try (final JMXConnector connector = JMXConnectorFactory.connect(url)) {
      final MBeanServerConnection mbsc = connector.getMBeanServerConnection();
      final RuntimeMXBean rmbean =
          ManagementFactory.newPlatformMXBeanProxy(
              mbsc, ManagementFactory.RUNTIME_MXBEAN_NAME, RuntimeMXBean.class);
      return Long.parseLong(rmbean.getName().split("@")[0]);
    } catch (final Throwable ignored) {
      return -1;
    }
  }
@return The native process ID of the process, -1 if failure.
integration-test/src/main/java/org/apache/iotdb/it/env/cluster/node/AbstractNodeWrapper.java