code: public static String wrap(final String str, final char wrapWith) {
  
          if (isEmpty(str) || wrapWith == CharUtils.NUL) {
              return str;
          }
  
          return wrapWith + str + wrapWith;
      }
docs: <p>
  Wraps a string with a char.
  </p>
  
  <pre>
  StringUtils.wrap(null, *)        = null
  StringUtils.wrap("", *)          = ""
  StringUtils.wrap("ab", '\0')     = "ab"
  StringUtils.wrap("ab", 'x')      = "xabx"
  StringUtils.wrap("ab", '\'')     = "'ab'"
  StringUtils.wrap("\"ab\"", '\"') = "\"\"ab\"\""
  </pre>
  
  @param str
  the string to be wrapped, may be {@code null}
  @param wrapWith
  the char that will wrap {@code str}
  @return the wrapped string, or {@code null} if {@code str==null}
  @since 3.4