if ((peekct & CT_ALPHA) != 0) {
            int i = 0;
            do {
                if (i >= buf.length) {
                    final char[] nb = new char[buf.length * 2];
                    System.arraycopy(buf, 0, nb, 0, buf.length);
                    buf = nb;
                }
                buf[i++] = (char) peekc;
                peekc = read();

        assertEquals("4", "a234a", StringUtil.replace("12341", "1", "a"));
        assertEquals("5", "ab234abab234ab", StringUtil.replace("1234112341", "1", "ab"));
        assertEquals("6", "a\\nb", StringUtil.replace("a\nb", "\n", "\\n"));
    }

    /**
     * @throws Exception
     */
    @Test
    public void testSplit() throws Exception {
        final String[] array = StringUtil.split("aaa\nbbb", "\n");