### Question:
TreePath implements Comparable<TreePath>, Serializable { @Override public String toString() { StringBuilder result = new StringBuilder(pathLength); for (int i = 0; i < pathLength; i++) { result.append(isLeftAt(i) ? '0' : '1'); } return result.toString(); } private  TreePath(long leftRight, int pathLength); @Override int hashCode(); @Override boolean equals(Object o); @Override String toString(); @Override int compareTo(TreePath o);  }### Answer:
@Test public void testToString() { assertEquals("", TreePath.EMPTY.toString()); assertEquals("010", LRL.toString()); assertEquals("011", LRR.toString()); }