public boolean isService() {
    return (service == 1);
  }
Indicates whether this KerberosPrincipalEntity represents a service principal (true) or not (false)

@return true if this KerberosPrincipalEntity represents a service principal; otherwise false
ambari-server/src/main/java/org/apache/ambari/server/orm/entities/KerberosPrincipalEntity.java