code: @NonNull
      public ReplicatorConfiguration setChannels(List<String> channels) {
          if (readonly) { throw new IllegalStateException("ReplicatorConfiguration is readonly mode."); }
          this.channels = channels;
          return getReplicatorConfiguration();
      }
docs: Sets a set of Sync Gateway channel names to pull from. Ignored for
  push replication. If unset, all accessible channels will be pulled.
  Note: channels that are not accessible to the user will be ignored
  by Sync Gateway.
  
  @param channels The Sync Gateway channel names.
  @return The self object.