### Question:
IrisFileName { public static Boolean containsInvalidCharacter(String fileName) { int len = fileName.codePointCount(0, fileName.length()); for (int i = 0; i < len; i++) { int c = fileName.codePointAt(i); if (Arrays.binarySearch(INVALID_CHARS, c) >= 0) { return true; } } return false; }  static Boolean containsInvalidCharacter(String fileName); static String clean(String fileName, String invalidCharReplacement); static boolean isValid(String fileName); static final int MAX_FILENAME_LENGTH; }### Answer:
@Test public void testContainsInvalidCharacter() { Boolean result = IrisFileName.containsInvalidCharacter("good.txt"); Assert.assertFalse(result); result = IrisFileName.containsInvalidCharacter("foo-ä-€.html"); Assert.assertFalse(result); result = IrisFileName.containsInvalidCharacter("fdgjnhg?,.html"); Assert.assertTrue(result); }