code: @Override
      public void setReasonPhrase(byte[] reason) {
          this.myReasonBytes = reason;
          this.myReason = null;
          super.setFirstLineChanged();
          if (TraceComponent.isAnyTracingEnabled() && tc.isEventEnabled()) {
              this.myReason = GenericUtils.getEnglishString(reason);
              Tr.event(tc, "setReasonPhrase(byte[]): set to [" + this.myReason + "]");
          }
      }
docs: Set the reason phrase of this response message.
  
  @param reason