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Java和简单json_Java_Json - Fatal编程技术网

Java和简单json

Java和简单json,java,json,Java,Json,我试图从一个json用户名中获取这是json [{"user_id":"1","username":"THEUSERNAME","count300":"0","count100":"0","count50":"0","playcount":"0","ranked_score":"0","total_score":"0","pp_rank":"0","level":"0","pp_raw":"0","accuracy":"0","count_rank_ss":"0","count_rank_s":

我试图从一个json用户名中获取这是json

[{"user_id":"1","username":"THEUSERNAME","count300":"0","count100":"0","count50":"0","playcount":"0","ranked_score":"0","total_score":"0","pp_rank":"0","level":"0","pp_raw":"0","accuracy":"0","count_rank_ss":"0","count_rank_s":"0","count_rank_a":"0","country":"0","events":[]}]
我的代码是

URL url = new URL("url");
        URLConnection c = url.openConnection();
        BufferedReader in = new BufferedReader(new InputStreamReader(c.getInputStream()));
        StringBuilder b = new StringBuilder();
        String line;
        while ((line = in.readLine()) != null) b.append(line);
        String text = b.toString();
        JSONParser jsonParser = new JSONParser();
        JSONObject jsonObject = (JSONObject) jsonParser.parse(text);
        String username = (String) jsonObject.get("username");
        System.out.println(username);
我得到的错误是什么

Exception in thread "main" java.lang.ClassCastException: org.json.simple.JSONArray cannot be cast to org.json.simple.JSONObject
at eu.dpp.ircbot.Ircbot.main(Ircbot.java:80)

注意原始字符串周围的[]。这表明它是一个JSONArray而不是一个JSONObject,这正是您得到的异常告诉您的。有关JSON规范,请参阅


实际对象被{}包围,您可能会感到困惑,因为数组中只有一个对象。但是您仍然必须将字符串视为数组,然后在其中的对象上迭代。

请注意原始字符串周围的[]。这表明它是一个JSONArray而不是一个JSONObject,这正是您得到的异常告诉您的。有关JSON规范,请参阅


实际对象被{}包围,您可能会感到困惑,因为数组中只有一个对象。但是您仍然必须将字符串视为数组,然后在其中的对象上迭代。

关于错误,您还不了解什么?您知道JSON格式吗?请阅读以下内容:关于错误,您不了解什么?您知道JSON格式吗?请阅读以下内容: