签名生成 参数名ASCII码从小到大排序

public static void main(String[] args) {
       SortedMap<Object,Object> parameters = new TreeMap<Object,Object>();
       //String mfrchant_id="fffff";
       String merchant_id="190010002";
       String business_type="1005";
       String out_trade_no="1400000001";
       String key="3A4BC4A4000CF1B5FFA9E351E6C1539E";
       //parameters.put("mfrchant_id", mfrchant_id);
       parameters.put("merchant_id", merchant_id);
       parameters.put("business_type", business_type);
       parameters.put("out_trade_no",out_trade_no);
       String characterEncoding = "UTF-8";         //指定字符集UTF-8
       String mySign = createSign(characterEncoding,parameters,key);
       //System.out.println("我 的签名是："+mySign);
   }
public static String createSign(String characterEncoding,SortedMap<Object,Object> parameters,String key){
    StringBuffer sb = new StringBuffer();
    StringBuffer sbkey = new StringBuffer();
    Set es = parameters.entrySet();  //所有参与传参的参数按照accsii排序（升序）
    Iterator it = es.iterator();
    while(it.hasNext()) {
        Map.Entry entry = (Map.Entry)it.next();
        String k = (String)entry.getKey();
        Object v = entry.getValue();
        //空值不传递，不参与签名组串
        if(null != v && !"".equals(v)) {
            sb.append(k + "=" + v + "&");
            sbkey.append(k + "=" + v + "&");
        }
    }
    //System.out.println("字符串:"+sb.toString());
    sbkey=sbkey.append("key="+key);
    System.out.println("字符串:"+sbkey.toString());
    //MD5加密,结果转换为大写字符
    String sign = MD5Util.MD5Encode(sbkey.toString(), characterEncoding).toUpperCase();
    System.out.println("MD5加密值:"+sign);
    return sb.toString()+"sign="+sign;
}
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作者：chenghaibing2008
来源：CSDN
原文：https://blog.csdn.net/chenghaibing2008/article/details/79701773
版权声明：本文为博主原创文章，转载请附上博文链接！

签名生成 参数名ASCII码从小到大排序
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