### Question:
ValidationUtils { public static void isGreaterThan(Number value, String property, String messagePrefix, Number min, Errors error) { if (value == null || value.doubleValue() <= min.doubleValue()) { error.rejectValue(property, messagePrefix + " should be greater than " + min); } }  static void isNotEmpty(String value, String property, String messagePrefix, int length, Errors error); static void isEmpty(String value, String property, String messagePrefix, Errors error); static void isNotLongerThan(String value, String property, String messagePrefix, int length, Errors error); static void isNotEmpty(Collection collection, String property, String errorMessage, Errors error); static void isNotNull(Object value, String property, String messagePrefix, Errors error); static void isNull(Object value, String property, String messagePrefix, Errors error); static void contains(String sequence, String searchSequence, String property, String messagePrefix, Errors error); static void isGreaterThan(Number value, String property, String messagePrefix, Number min, Errors error); static void isGreaterOrEqualTo(Number value, String property, String messagePrefix, Number min, Errors error); static void isBetween(Number value, String property, String messagePrefix, Number min, Number max, Errors error); static void isBetweenInclusive(Number value, String property, String messagePrefix, Number min, Number max, Errors error); static void isNullOrGreaterOrEqualTo(Number value, String property, String messagePrefix, Number min, Errors error); static void isNullOrGreaterThan(Number value, String property, String messagePrefix, Number min, Errors error); static void isDefined(P entity, R repository, String property, String messagePrefix, Errors error); static void isAfter(Date value, String property, String messagePrefix, Date otherDate, Errors error); static boolean isAnId(@Null final String string); static void entityExists(Long id, CrudRepository repository, String property, String messagePrefix, Errors
            error);  }### Answer:
@Test public void shouldIsGreaterThanNotAcceptNullValue() throws Exception { ValidationUtils.isGreaterThan(null, property, messagePrefix, 0, error); verify(error).rejectValue(eq(property), and(startsWith(messagePrefix), endsWith("0"))); }
@Test public void shouldIsGreaterThanNotAcceptSmallerValue() throws Exception { ValidationUtils.isGreaterThan(-1, property, messagePrefix, 0, error); verify(error).rejectValue(eq(property), and(startsWith(messagePrefix), endsWith("0"))); }
@Test public void shouldIsGreaterThanNotAcceptEqualValue() throws Exception { ValidationUtils.isGreaterThan(0, property, messagePrefix, 0, error); verify(error).rejectValue(eq(property), and(startsWith(messagePrefix), endsWith("0"))); }
@Test public void shouldIsGreaterThanAcceptValidValue() throws Exception { ValidationUtils.isGreaterThan(1, property, messagePrefix, 0, error); verify(error, times(0)).rejectValue(anyString(), anyString()); }