### Question:
Strings { public static String stripTrailingSlash(String s) { return s == null ? null : CharMatcher.is('/').trimTrailingFrom(s); }  static boolean isEmptyOrWhitespace(String string); static boolean isEmptyOrNull(List<String> list); static boolean isWhitelisted(String item, List<String> whitelist); static String stripLeadingSlash(String s); static String stripTrailingSlash(String s); static String stripSlash(String s);  }### Answer:
@Test public void testStripTrailingSlash() { assertNull(Strings.stripLeadingSlash(null)); assertEquals("string", Strings.stripTrailingSlash("string")); assertEquals( "stringWithTrailingSlash", Strings.stripTrailingSlash("stringWithTrailingSlash/")); }