code: public void setPreferredNodeIdPrefix(String preferredNodeIdPrefix) {
          LettuceAssert.notNull(preferredNodeIdPrefix, "preferredNodeIdPrefix must not be null");
          boolean resetRoundRobin = false;
  
          if (this.preferredNodeIdPrefix == null || !preferredNodeIdPrefix.equals(this.preferredNodeIdPrefix)) {
              resetRoundRobin = true;
          }
  
          this.preferredNodeIdPrefix = preferredNodeIdPrefix;
  
          if (resetRoundRobin) {
              resetRoundRobin(preferredNodeIdPrefix);
          }
      }
docs: Set the id prefix of the preferred node.
  
  @param preferredNodeIdPrefix the id prefix of the preferred node