### Question:
RegexUtil { public static String obfuscateEmail(String str) { Matcher emailMatch = EMAIL_PATTERN.matcher(str); while (emailMatch.find()) { String at = emailMatch.group(1); str = str.replaceFirst(at, "-AT-"); String dot = emailMatch.group(2) + emailMatch.group(3) + emailMatch.group(4); String newDot = emailMatch.group(2) + "-DOT-" + emailMatch.group(4); str = str.replaceFirst(dot, newDot); } return str; }  static String encodeEmail(String str); static String obfuscateEmail(String str); static List<String> getMatches(Pattern pattern, String match, int group); static String encode(String email); static final Pattern MAILTO_PATTERN; static final Pattern EMAIL_PATTERN; }### Answer:
@Test public void testObfuscateEmail() { String test = "this@email.com"; String expect = "this-AT-email-DOT-com"; String result = RegexUtil.encodeEmail(test); assertEquals(expect, result); }