RBLL { public int size() { return tree.size(); }  @Override boolean equals(Object o); @Override int hashCode(); boolean containsInt(int elem); LibBasedNode getIntervalContaining(int elem); @Override String toString(); int size(); void clear(); void addInterval(int start, int end); static void main(String[] args);  }
@Test public void testSize() throws Exception { assertEquals(0, rbll.size()); rbll.addInterval(0, 4); assertEquals(1, rbll.size()); }