### Question:
RangeSet implements IRangeSet<E> { @Override public boolean contains(Object o) { @SuppressWarnings("unchecked") E e = (E)o; Range<E> f = ranges.floor(createRange(e,e)); return f != null && f.contains(e); } RangeSet();  RangeSet(IEnumerator<E> enumerator); @Override int getNumberOfRanges(); @Override Iterator<Range<E>> rangeIterator(); @Override List<Range<E>> toRangeList(); @Override int approximateSize(); @Override boolean addRange(E first, E last); @Override boolean removeRange(E first, E last); @Override int size(); @Override boolean isEmpty(); @Override boolean contains(Object o); @Override Iterator<E> iterator(); @Override Object[] toArray(); @SuppressWarnings("unchecked") @Override T[] toArray(T[] a); @Override boolean add(E e); @Override boolean remove(Object o); @Override boolean containsAll(Collection<?> c); @Override boolean addAll(Collection<? extends E> c); @Override boolean retainAll(Collection<?> c); @Override boolean removeAll(Collection<?> c); @Override void clear(); boolean equals(Object o); int hashCode(); String toString();  }### Answer:
@Test public void testContains() { CheckedRangeSet<Integer> set = randomCheckedRangeSet(-100, 100, 10); for (int i = 0; i < 20; i++) set.contains(random(-150, 150)); }