String userStr=readJSONString(request);
System.out.println(userStr);//能輸出
JSONObject jsonObj = JSONObject.fromObject(userStr);//我感覺(jué)這有問(wèn)題
System.out.println(jsonObj.getInt("userid"));//后臺(tái)沒(méi)輸出
System.out.println(jsonObj.getString("username"));
輸出結(jié)果如下
4
0
0
光陰似箭催人老，日月如移越少年。
should be JSONObject import錯(cuò)了，或者是版本不對(duì)吧，我本地用的是 json-lib-2.4 net.sf.json.JSONObject, which is OK.
If the frontend transmits json type data, then the backend receives json type data, and there is no need to transfer it anymore
1. First confirm whether your userStr is a json string:
For example: String jstr="{'json':'jsonvalue','bool':true,'int':1,'double':'20.5'} ";
2. Then check whether the JOSNObject you are using is the json.jar package.
3. Confirm whether your json package is imported correctly.
First take a look at the package introduction of the net.sf.json.JSONObject version mentioned by taomaokun, and then check whether your json string is written correctly. This is generally available
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