code: public Subscription withEventSubscriptions(EventSubscription... eventSubscriptions) {
          if (this.eventSubscriptions == null) {
              setEventSubscriptions(new java.util.ArrayList<EventSubscription>(eventSubscriptions.length));
          }
          for (EventSubscription ele : eventSubscriptions) {
              this.eventSubscriptions.add(ele);
          }
          return this;
      }
docs: <p>
  The list of existing event subscriptions.
  </p>
  <p>
  <b>NOTE:</b> This method appends the values to the existing list (if any). Use
  {@link #setEventSubscriptions(java.util.Collection)} or {@link #withEventSubscriptions(java.util.Collection)} if
  you want to override the existing values.
  </p>
  
  @param eventSubscriptions
  The list of existing event subscriptions.
  @return Returns a reference to this object so that method calls can be chained together.