int chunk = (bytes[i++] & 0xFF) << 16 | (bytes[i++] & 0xFF) << 8 | (bytes[i++] & 0xFF);
        target.append(alphabet.encode(chunk >>> 18));
        target.append(alphabet.encode((chunk >>> 12) & 0x3F));
        target.append(alphabet.encode((chunk >>> 6) & 0x3F));
        target.append(alphabet.encode(chunk & 0x3F));
      }
      if (i < off + len) {

        assertTrue(result.contains("Valid XML text 123"));
    }

    public void test_stripInvalidXMLCharacters_withInvalidChars() {
        // Test with invalid control characters (0x1-0x8, 0xB, 0xC, 0xE-0x1F)
        String input = "Test\u0001\u0002\u0008Valid\u000B\u000C\u000EText";
        String result = XmlUtil.stripInvalidXMLCharacters(input);
        assertEquals("TestValidText", result);
    }

    /**
     * UTF-7 Byte Order Mark definition.
     */
    protected static final ByteOrderMark BOM_UTF_7 = new ByteOrderMark("UTF-7", 0x2B, 0x2F, 0x76);

    /**
     * HTML4 unescape translator.
     */
    protected static final CharSequenceTranslator UNESCAPE_HTML4 = new AggregateTranslator(

     */
    public static void appendHex(final StringBuilder buf, final int i) {
        buf.append(Integer.toHexString(i >> 24 & 0xff));
        buf.append(Integer.toHexString(i >> 16 & 0xff));
        buf.append(Integer.toHexString(i >> 8 & 0xff));
        buf.append(Integer.toHexString(i & 0xff));
    }

    /**
     * Converts an underscore-separated string to camel case.
     * <p>
     * Usage example:

        <match value="0x01" mask="0x0F" type="string" offset="4"/>
      </match>
    </magic>
  </mime-type>
  <mime-type type="application/sereal;version=2">
    <sub-class-of type="application/sereal"/>
    <magic priority="50">
      <match value="0x6C72733D" type="little32" offset="0">
        <match value="0x02" mask="0x0F" type="string" offset="4"/>
      </match>
    </magic>