支付宝授权登录后台示例：API接口与加密实现

public ResultInfo<Object> authorizationLogin() throws AlipayApiException, UnsupportedEncodingException {
  SortedMap<String,String > map = new TreeMap<>();
  map.put("apiname","com.alipay.account.auth");
  map.put("method","alipay.open.auth.sdk.code.get");
  map.put("app_id",  支付宝分配给开发者的应用ID);
  map.put("app_name","mc");
  map.put("biz_type","openservice");
  map.put("pid",签约的支付宝账号对应的支付宝唯一用户号，以2088开头的16位纯数字组成);
  map.put("product_id","APP_FAST_LOGIN");
  map.put("scope","kuaijie");
  map.put("target_id",商户标识该次用户授权请求的ID，该值在商户端应保持唯一);//自定义
  map.put("auth_type","AUTHACCOUNT");
  map.put("sign_type","RSA");
  String signStr = AlipaySignature.getSignContent(map);
  String sign = AlipaySignature.rsaSign(signStr, 私钥, 编码);
  System.out.println(getMapToString(map) + "&sign=" + URLEncoder.encode(sign, 编码));
}


/* Map转String
 * @param map
 * @return */
public static String getMapToString(SortedMap<String, String> map) {
Set<String> keySet = map.keySet() ;
// 将set集合转换为数组
String [] keyArray = keySet.toArray(new String [keySet.size()]) ;
// 给数组排序(升序)
Arrays.sort(keyArray) ;
// 因为String拼接效率会很低的，所以转用StringBuilder
StringBuilder sb = new StringBuilder() ;