public JmxClient(){
  jmxUrl=Optional.empty();
  conn_=CompletableFuture.completedFuture(new GCCloseable<>(new LocalhostJMXConnectorStub()));
}

public JmxClient ( ) { jmxUrl = Optional . empty ( ) ; conn_ = CompletableFuture . completedFuture ( new GCCloseable < > ( new LocalhostJMXConnectorStub ( ) ) ) ; }
create a default client , using the default platformmbeanserver . this client is effectively connected to the jvm it is part of .
