### Question:
DeweyVersion { @Override public String toString() { return Arrays.stream(versions) .mapToObj(Integer::toString) .collect(Collectors.joining(".")); } DeweyVersion();  DeweyVersion(int run);  DeweyVersion(String s); private  DeweyVersion(int[] versions); DeweyVersion addRun(); int length(); boolean isCompatible(DeweyVersion that); DeweyVersion addStage(); @Override String toString();  }### Answer:
@Test public void testStringConstructor() { assertEquals(new DeweyVersion("1.0.1").toString(), "1.0.1"); }
@Test public void testDeweyVersionConstructor() { assertEquals("1", new DeweyVersion(1).toString()); }