### Question:
CommonUtil { public static String sanitize(String v) { if (v != null) { return v.toLowerCase().trim(); } return null; } private  CommonUtil(); static boolean isEmpty(List list); static boolean isBlank(String str); static String sanitize(String v); static String DateToDayString(Date date); static Date dayToDate(String day); static String convertToString(List<String> list); static Map convertToMap(Object object); static List<String> removeStringFromItems(List<String> list, String toRemove); static Integer determinePriceCatForCPM(double price); static Integer determinePriceCatForCPC(double price); static Integer determinePriceCatForCPD(double price); static Integer determinePriceCatForCPT(double price); static Integer determinePriceCat(double price, TargetingChannel.PriceModel priceModel); static String removeEscapingCharacters(String str); static boolean equalNumbers(double d1, double d2);  }### Answer:
@Test public void sanitize() { String s = null; assertNull(CommonUtil.sanitize(s)); s = "WAESDasweraq"; assertEquals("waesdasweraq", CommonUtil.sanitize(s)); s = "abc"; assertEquals("abc", CommonUtil.sanitize(s)); s = " sf - wWA wE_ + SD=14asdsSAD fweraq aA"; assertEquals("sf - wwa we_ + sd=14asdssad fweraq aa", CommonUtil.sanitize(s)); }