### Question:
FilterRange extends Range<T> { public static <T extends Comparable<? super T>> FilterRange<T> atMost(final T upperEndpoint) { return new FilterRange<>(null, Bound.inclusive(upperEndpoint)); } private  FilterRange(final Bound<T> lowerBound, final Bound<T> upperBound); static FilterRange<T> of(final T lowerEndpoint, final T upperEndpoint); static FilterRange<T> atMost(final T upperEndpoint); static FilterRange<T> atLeast(final T lowerEndpoint);  }### Answer:
@Test public void buildsFilterRangeLessThanOrEqualTo() throws Exception { final Range<Integer> range = FilterRange.atMost(4); final Bound<Integer> upperBound = range.upperBound(); assertThat(range.lowerBound()).isNull(); assertThat(upperBound.endpoint()).isEqualTo(4); assertThat(upperBound.isInclusive()).isTrue(); }