如何让URLEncoding不对冒号进行编码？

我有一个JSONObject：

I have a JSONObject:

{user:{"firstname":"testuser","surname":"æøå"}}

所以我在对象中有这些特殊字符

So i have these special characters in the object

I URLEncode我有的jsonString。

I URLEncode the jsonString i have.

urlEncodedJsonReq = URLEncoder.encode("{user:{\"firstname\":\"testuser\",\"surname\":\"æøå\"}}","UTF-8");

我收到服务器的回复：你提交的URI不允许使用字符。
这是编码的网址： serverurl /％7Buser％3A％7B％22firstname％22％3A％22testuser％22％2C％22sameame％22％3A％22％C3％A6％C3 ％B8％C3％A5％22％7D％7D

I get a response from the server: "The URI you submitted has disallowed characters.". This is the encoded url: serverurl/%7Buser%3A%7B%22firstname%22%3A%22testuser%22%2C%22surname%22%3A%22%C3%A6%C3%B8%C3%A5%22%7D%7D

但我需要的是：

%7Buser:%7B%22firstname%22:%22testuser%22%2C%22surname%22:%22%C3%A6%C3%B8%C3%A5%22%7D%7D

这是否可以以合理的方式实现？

Is this possible in any reasonable way?

提前致谢