@Test
public void testInstance() {

    DateValidator ts = DateValidator.instance();
    assertTrue(ts.validate("2015-01-15"));
    assertFalse(ts.validate("2015-01-15 11:00:15"));
    assertFalse(ts.validate("2015/01/15 11:10:20"));
    assertFalse(ts.validate("12/01/2015"));
    assertFalse(ts.validate("13/01/2015"));
}