code: public static <T> ValueHolder<T> withNonNullValue(final T value) {
      Assert.notNull(value, "The value must not be null!");
  
      return new ValueHolder<T>(value) {
        @Override
        public void setValue(final T value) {
          Assert.notNull(value, "The value must not be null!");
          super.setValue(value);
        }
      };
    }
docs: Factory method to construct an instance of the ValueHolder class with a non-null value.
  
  @param <T> the Class type of the Object value.
  @param value the non-null value to hold.
  @return a ValueHolder instance that enforces non-null values.
  @throws NullPointerException if the value is null.