code: public static MBeanServer getJolokiaMBeanServer() {
          MBeanServer server = ManagementFactory.getPlatformMBeanServer();
          MBeanServer jolokiaMBeanServer;
          try {
              jolokiaMBeanServer =
                      (MBeanServer) server.getAttribute(createObjectName(JolokiaMBeanServerHolderMBean.OBJECT_NAME),
                                                        JOLOKIA_MBEAN_SERVER_ATTRIBUTE);
          } catch (InstanceNotFoundException exp) {
              // should be probably locked, but for simplicity reasons and because
              // the probability of a clash is fairly low (can happen only once), it's omitted
              // here. Note, that server.getAttribute() itself is threadsafe.
              jolokiaMBeanServer = registerJolokiaMBeanServerHolderMBean(server);
          } catch (JMException e) {
              throw new IllegalStateException("Internal: Cannot get JolokiaMBean server via JMX lookup: " + e,e);
          }
          return jolokiaMBeanServer;
      }
docs: Lookup the JolokiaMBean server via a JMX lookup to the Jolokia-internal MBean exposing this MBeanServer
  
  @return the Jolokia MBeanServer or null if not yet available present