#fixed code
                                private static String getCardCodec(File cardDir) {
        String cardCodec = "";
        File[] cardFiles = cardDir.listFiles();
        if (cardFiles == null) {
            return "";
        }
        for (File file : cardDir.listFiles()) {
            if (file.getName().startsWith("codec")) {
                cardCodec = FileUtil.getKeyValueMapFromFile(file.getPath(), ":").get("Codec");
            }
        }
        return cardCodec;
    }
#vulnerable code 
                                private static String getCardCodec(File cardDir) {
        String cardCodec = "";
        for (File file : cardDir.listFiles()) {
            if (file.getName().startsWith("codec")) {
                cardCodec = FileUtil.getKeyValueMapFromFile(file.getPath(), ":").get("Codec");
            }
        }
        return cardCodec;
    } 
                            #location 3 
                            #vulnerability type NULL_DEREFERENCE