guava/src/com/google/common/collect/GeneralRange.java
static <T> GeneralRange<T> all(Comparator<? super T> comparator) {
    return new GeneralRange<T>(comparator, false, null, OPEN, false, null, OPEN);
  }
static <T> GeneralRange<T> all(Comparator<? super T> comparator) {
    return new GeneralRange<T>(comparator, false, null, OPEN, false, null, OPEN);
  }
Returns the whole range relative to the specified comparator.