### Question:
CommonUtils { public static int parseInt(String num, int defaultInt) { if (num == null) { return defaultInt; } else { try { return Integer.parseInt(num); } catch (Exception e) { return defaultInt; } } }  static V putToConcurrentMap(ConcurrentMap<K, V> map, K key, V value); static boolean isTrue(String b); static boolean isTrue(Boolean b); static boolean isFalse(Boolean b); static boolean isFalse(String b); static boolean isEmpty(Collection collection); static boolean isNotEmpty(Collection collection); static boolean isEmpty(Map map); static boolean isNotEmpty(Map map); static boolean isEmpty(Object[] array); static boolean isNotEmpty(Object[] array); static T parseNum(T num, T defaultInt); static int parseInt(String num, int defaultInt); static long parseLong(String num, long defaultLong); static boolean parseBoolean(String bool, boolean defaultInt); static int[] parseInts(String nums, String sperator); static boolean listEquals(List<T> left, List<T> right); static String join(Collection collection, String separator);  }### Answer:
@Test public void testParseInt() { Assert.assertEquals(CommonUtils.parseInt("", 123), 123); Assert.assertEquals(CommonUtils.parseInt("xxx", 123), 123); Assert.assertEquals(CommonUtils.parseInt(null, 123), 123); Assert.assertEquals(CommonUtils.parseInt("12345", 123), 12345); }