code: public static boolean containsNone(final CharSequence cs, final String invalidChars) {
          if (cs == null || invalidChars == null) {
              return true;
          }
          return containsNone(cs, invalidChars.toCharArray());
      }
docs: <p>Checks that the CharSequence does not contain certain characters.</p>
  
  <p>A {@code null} CharSequence will return {@code true}.
  A {@code null} invalid character array will return {@code true}.
  An empty String ("") always returns true.</p>
  
  <pre>
  StringUtils.containsNone(null, *)       = true
  StringUtils.containsNone(*, null)       = true
  StringUtils.containsNone("", *)         = true
  StringUtils.containsNone("ab", "")      = true
  StringUtils.containsNone("abab", "xyz") = true
  StringUtils.containsNone("ab1", "xyz")  = true
  StringUtils.containsNone("abz", "xyz")  = false
  </pre>
  
  @param cs  the CharSequence to check, may be null
  @param invalidChars  a String of invalid chars, may be null
  @return true if it contains none of the invalid chars, or is null
  @since 2.0
  @since 3.0 Changed signature from containsNone(String, String) to containsNone(CharSequence, String)