RangeBoundary implements Comparable<RangeBoundary<C>> { boolean isPlusInfinity() { return infinity && infinitySign > 0; } private  RangeBoundary(C value, boolean infinity, int infinitySign);  RangeBoundary(C value); @Override int compareTo(RangeBoundary<C> other); @Override String toString(); @Override int hashCode(); @Override boolean equals(Object obj);  }
@Test public void shouldCreatePlusInfinitiBoundaryWhenNullValuePassed() { RangeBoundary<Integer> boundary = new RangeBoundary<Integer>(null); assertThat(boundary.isPlusInfinity()).isTrue(); }