code: public void startAll() throws Exception {
          // Make sure the child processes and any created files get killed/deleted if the process is terminated.
          this.cleanup.set(new Thread(this::cleanupOnShutdown));
          Runtime.getRuntime().addShutdownHook(this.cleanup.get());
  
          if (this.startZk) {
              resumeZooKeeper();
          }
  
          initializeZookeeper();
          runBookies();
      }
docs: Starts the BookKeeper cluster in-process.
  
  @throws Exception If an exception occurred.