java - 表达式的类型必须是数组类型，但它解析为 JSONArray

Question

我得到一个 JSON 对象，然后将其转换为数组并尝试访问属性或值，但收到错误 表达式的类型必须是数组类型，但它解析为 JSONArray

我必须将 JSON 数据保存到我的数据库中，这就是为什么我要获取数组中的所有值

我的代码

protected void doPost(HttpServletRequest request, HttpServletResponse response)
        throws ServletException, IOException {

    Scanner scanner = new Scanner(request.getInputStream());
    String imageData = scanner.nextLine();
    System.out.println(imageData);
    JSONObject jsonObj = new JSONObject(imageData);
    JSONArray jsonArray = jsonObj.getJSONArray("ImageData");

    JSONObject innerObj = new JSONObject(jsonArray[0]); // this one is throwing error 
    // eror is `The type of the expression must be an array type but it resolved to JSONArray`
    String counter = innerObj.getString("Counter");
    String name = innerObj.getString("Name");
    String isActive = innerObj.getString("IsActive");     
    System.out.println(counter);

}

System.out.println(imageData); it prints -->

{"ImageData":[{"计数器":"计数器 A","名称":"CountA1.jpg","IsActive":"Y"},{"计数器":"计数器 A","名称":"CountA2.jpg","IsActive":"Y"}]}

System.out.println(jsonArray);这个打印 -->

[{"计数器":"计数器 A","IsActive":"Y","名称":"CountA1.jpg"},{"计数器":"计数器 A","IsActive": "Y","名称":"CountA2.jpg"}]

我已经评论了代码中出现错误的行

Answer 1

使用getJSONObject方法

JSONObject innerObj =  jsonArray.getJSONObject(0);

Returns the value at index if it exists and is a JSONObject.