@JsonIgnore
    public String toJson() throws IOException {
      ObjectMapper mapper = new ObjectMapper();
      mapper.configure(SerializationFeature.FAIL_ON_EMPTY_BEANS, false);
      return mapper.writerWithDefaultPrettyPrinter().writeValueAsString(this);
    }
Returns all HS2 instances in Active-Passive standy modes.
service/src/java/org/apache/hive/service/servlet/HS2Peers.java