PHP DES encryption and decryption method code

<?php
require_once(&#39;Des.php&#39;);

$des = new Des();

$data[&#39;a&#39;] = &#39;a&#39;;
$data[&#39;b&#39;] = &#39;b&#39;;

$conf = [&#39;appkey&#39;=>&#39;AbcdefghijklmnopqrstuvwX&#39;,&#39;secretcode&#39;=>&#39;Abcdefgh&#39;];

$encode = $des->encode($data, $conf);

print_r($encode);
echo "<br>";

$decode = $des->decode($encode,$conf);

print_r($decode);

?>

<?php

require_once(&#39;TripleDES.php&#39;);

class Des {

    public static function encode($data, $configKey) {
        $tripleDes = new TripleDES();
        if (is_array($data)) {
            $data = json_encode($data);
        }
        return $tripleDes->encode($data, $configKey["appkey"], $configKey["secretcode"]);
    }

    public static function decode($data, $configKey) {
        $tripleDes = new TripleDES();
        return $tripleDes->decode($data, $configKey["appkey"], $configKey["secretcode"]);
    }

    public static function encodeArr($data, $configKey) {
        $data = json_encode($data);
        return self::encode($data, $configKey);
    }

    public static function decodeArr($data, $configKey) {
        $res = self::decode($data, $configKey);
        return json_decode($res,true);
    }

}