例如 ： 
{"nonce":"shinx","timestamp":"20210727141938","appKey":"OiW6txJ8AZ1WkJPYFmxx","appSecret":"yVvXJM0SvFZuBRpCmGwK"}
    MD5("shinx20210727141938OiW6txJ8AZ1WkJPYFmxxyVvXJM0SvFZuBRpCmGwK)  
生成sign为： c0e6a1e4d125bf4cfc01a933ced8f5e5
            

URI    调用接口时不同接口使用不同uri  
sign  根据SIGN 生成规则生成
secret  卓鹰平台提供接口秘钥，值为 RICH_ZY   

例如：2.1 模版创建接口  则所需 加签字符为    
/v1/api/rich/template/createc0e6a1e4d125bf4cfc01a933ced8f5e5
​
加签后字符为  
YmRjMmVkNmZiODIyZTYxMjRhYzk4NjQ5NTY5MzM2MzkyNzc3OWNhMGRjY2NiMzQ5NThiYzc2NzllMGQwMzA1Mg%3D%3D

private static String byteToHex(byte[] bytes) {
    if (bytes == null)  return null;
    StringBuffer stringBuffer = new StringBuffer();
    String temp = null;
    for (int i = 0; i < bytes.length; i++) {
        temp = Integer.toHexString(bytes[i] & 0xff);
        if (temp.length() == 1) {
            stringBuffer.append("0");
        }
        stringBuffer.append(temp);
    }
    return stringBuffer.toString();
}
​
public static void main(String[] args) {
    try {
        String secret="RICH_ZY";
        String message="/v1/api/rich/template/createc0e6a1e4d125bf4cfc01a933ced8f5e5";
        Mac sha256_HMAC = Mac.getInstance("HmacSHA256");
        SecretKeySpec secretKey = new SecretKeySpec(secret.getBytes("utf-8"), "HmacSHA256");
        sha256_HMAC.init(secretKey);
        byte[] hash = sha256_HMAC.doFinal(message.getBytes("utf-8"));
        String SHA256 = byteToHex(hash);
        String encodeStr = Base64.getEncoder().encodeToString(SHA256.getBytes("utf-8"));
        String Authorization = URLEncoder.encode(encodeStr, "utf-8");
        System.out.println(Authorization);
    } catch (Exception e) {
​
    }
}