第一种(java8):遍历JSONArray 拼接字符串

public static void main(String[] args) {
        
        JSONArray jSONArray = new JSONArray();
        JSONObject jb = new JSONObject();
        jb.put("id", 1);
        jb.put("name", "s");
        jSONArray.add(jb);
        JSONObject j1 = new JSONObject();
        j1.put("id", 2);
        j1.put("name", "s");
        jSONArray.add(j1);
        StringBuffer sBuffer = new StringBuffer();
        jSONArray.stream().forEach(jsonobejct->arrayIdToString((JSONObject) jsonobejct,sBuffer));
        System.out.println(sBuffer.toString());
    }

    private static StringBuffer arrayIdToString(JSONObject jsonobejct,
            StringBuffer sBuffer) {
        return sBuffer.append(jsonobejct.getInteger("id")).append(",");
    }

 第二种:for循环遍历

public static void f2(JSONArray ja) {
        for(int i=0;i<ja.size();i++) {
            System.out.println(ja.getJSONObject(i).get("id"));
        }
    }