code: public static boolean isNullOrEmpty(Object obj) {
          if (obj == null)
              return true;
          if (obj instanceof String) {
              return (((String) obj).isEmpty());
          }
          if (obj instanceof Map) {
              return ((Map) obj).isEmpty();
          }
          if (obj instanceof List) {
              return ((List) obj).isEmpty();
          }
          if (obj instanceof Set) {
              return ((Set) obj).isEmpty();
          }
          return false;
      }
docs: Returns true if object is null or empty
  
  @param obj
  @return