生成MD5只有31位如何解决？

public staticString toMd5(File file) {
        String value = null;
        byte[] encrypt;
        FileInputStream in = null;
        try{
            in = newFileInputStream(file);
            MappedByteBuffer byteBuffer = in.getChannel().map(FileChannel.MapMode.READ_ONLY, 0, file.length());
            MessageDigest md5 = MessageDigest.getInstance("MD5");
            md5.update(byteBuffer);
            encrypt =md5.digest();
            StringBuilder sb = newStringBuilder();
            for (bytet : encrypt) {
                sb.append(Integer.toHexString(t & 0xFF));
            }
            value =sb.toString();
        } catch(Exception e) {
            e.printStackTrace();
        }
        returnvalue;
    }

public staticString toMd5(File file) {
        String value = null;
        byte[] encrypt;
        FileInputStream in = null;
        try{
            in = newFileInputStream(file);
            MappedByteBuffer byteBuffer = in.getChannel().map(FileChannel.MapMode.READ_ONLY, 0, file.length());
            MessageDigest md5 = MessageDigest.getInstance("MD5");
            md5.update(byteBuffer);
            encrypt =md5.digest();
            StringBuilder sb = newStringBuilder();
            for (bytet : encrypt) {
                String s = Integer.toHexString(t & 0xFF);
                if (s.length() == 1) {
                    s = "0" + s; //注意此行，如果只有一位，在首位加0
}
                sb.append(s);
            }
            value =sb.toString();
        } catch(Exception e) {
            e.printStackTrace();
        }
        returnvalue;
    }