### Question:
VersionToken implements Comparable<VersionToken>, Iterator<VersionToken>, Serializable { public synchronized VersionToken next() { final int[] newValues = Arrays.copyOf(segments, segments.length + 1); newValues[newValues.length - 1] = next++; return new VersionToken(newValues); } private  VersionToken(int[] segments);  VersionToken(int value); static VersionToken apply(int[] segments, int nextSegment); int getFirstSegment(); int length(); int[] getSegments(); synchronized VersionToken next(); int nextSegment(); boolean hasNext(); void remove(); String toString(); boolean equals(Object o); int hashCode(); @Override int compareTo(VersionToken that); static VersionToken valueOf(String stringValue); static int[] segments(String stringValue);  }### Answer:
@Test public void testComparable() { final VersionToken vt1 = new VersionToken(1); final VersionToken vt1_1 = vt1.next(); final VersionToken vt1_1_1 = vt1_1.next(); final VersionToken vt1_1_2 = vt1_1.next(); final VersionToken vt1_1_3 = vt1_1.next(); final VersionToken vt1_2 = vt1.next(); final VersionToken vt1_2_1 = vt1_2.next(); final VersionToken vt1_2_2 = vt1_2.next(); final VersionToken vt1_2_3 = vt1_2.next(); final VersionToken vt2 = new VersionToken(2); final VersionToken vt2_1 = vt2.next(); final VersionToken vt2_1_1 = vt2_1.next(); final VersionToken[] tokens = new VersionToken[]{ vt2_1, vt1_1_1, vt1_2_1, vt2, vt1_1_3, vt1_2_2, vt1_2, vt2_1_1, vt1_1, vt1_1_2, vt1_2_3, vt1, }; Arrays.sort(tokens); final VersionToken[] expected = new VersionToken[]{ vt1, vt1_1, vt1_1_1, vt1_1_2, vt1_1_3, vt1_2, vt1_2_1, vt1_2_2, vt1_2_3, vt2, vt2_1, vt2_1_1, }; assertArrayEquals(expected, tokens); }