### Question:
IntegerUtil { public static boolean isZero(final Integer value) { return value != null && value.intValue() == 0; } private  IntegerUtil(); static boolean isNotZero(final Integer value); static boolean isZero(final Integer value); static boolean isNullOrZero(final Integer value); static boolean isSameValue(final Integer val1, final Integer val2); static boolean isNotSameValue(final Integer val1, final Integer val2); static Integer safeAdd(final Integer v1, final Integer v2); static int safeSignum(final Integer v); static int safeCompare(final Integer id, final Integer id2); static Integer assign(final Integer value, final Integer defaultValueIfNull); static boolean isNotZeroOrNegative(final Integer id);  }### Answer:
@Test public void testIsZero() { assertThat(isZero(0)).isTrue(); assertThat(isZero(null)).isFalse(); assertThat(isZero(1)).isFalse(); }