code: public RiakNode setBootstrap(Bootstrap bootstrap)
      {
          stateCheck(State.CREATED);
          if (this.bootstrap != null)
          {
              throw new IllegalArgumentException("Bootstrap already set");
          }
  
          this.bootstrap = bootstrap.clone();
          return this;
      }
docs: Sets the Netty {@link Bootstrap} for this Node's connections.
  {@link Bootstrap#clone()} is called to clone the bootstrap.
  
  @param bootstrap - the Netty Bootstrap to use
  @return a reference to this RiakNode
  @throws IllegalArgumentException if it was already set via the builder.
  @throws IllegalStateException    if the node has already been started.
  @see Builder#withBootstrap(io.netty.bootstrap.Bootstrap)