在Android上使用GSON解析JSON

Question

我已经成功解析了http://kylewbanks.com/rest/将此数据发布到我的Android应用程序中。

此JSON的格式为

[
{...},
{...},
{...}
]

我的问题是我需要以以下格式解析JSON：

{
"count":3,
"result":[
{...},
{...},
{...}
]
}

我知道我需要超越计数和结果，而只解析arraylist。 关于如何使用GSON的任何想法。 我需要循环查找吗？ 还是有另一种方法？

我的背景

    @Override
    protected String doInBackground(Void... params) {
        try {
            //Create an HTTP client
            HttpClient client = new DefaultHttpClient();
            HttpPost post = new HttpPost(SERVER_URL);

            //Perform the request and check the status code
            HttpResponse response = client.execute(post);
            StatusLine statusLine = response.getStatusLine();
            if(statusLine.getStatusCode() == 200) {
                HttpEntity entity = response.getEntity();
                InputStream content = entity.getContent();

                try {
                    //Read the server response and attempt to parse it as JSON
                    Reader reader = new InputStreamReader(content);

                    GsonBuilder gsonBuilder = new GsonBuilder();
                    gsonBuilder.setDateFormat("M/d/yy hh:mm a");
                    Gson gson = gsonBuilder.create();
                    List<Post> posts = new ArrayList<Post>();
                    posts = Arrays.asList(gson.fromJson(reader, Post[].class));
                    content.close();

                    handlePostsList(posts);
                } catch (Exception ex) {
                    Log.e(TAG, "Failed to parse JSON due to: " + ex);
                    failedLoadingPosts();
                }
            } else {
                Log.e(TAG, "Server responded with status code: " + statusLine.getStatusCode());
                failedLoadingPosts();
            }
        } catch(Exception ex) {
            Log.e(TAG, "Failed to send HTTP POST request due to: " + ex);
            failedLoadingPosts();
        }
        return null;
    }

Answer 1

JSONArray notificationsArray = response.getJSONArray("array_name");
Model_Name[] model_name = new Gson().fromJson(notificationsArray.toString(), Model_Name[].class);

使用GSON解析JSON的简单方法

Answer 2

您应该创建类来包装整个结构，例如。

class Result {
    private int count;
    private Post[] posts;
    // getters,setters
}

而不是

 posts = Arrays.asList(gson.fromJson(reader, Post[].class));

写

result = gson.fromJson(reader, Result.class)

比从结果对象获取数组

Answer 3

将您的对象作为基本JsonObject读取，然后获取名为“ result”的JsonElement并将其传递给gson：

JsonObject root = new JsonParser().parse(reader).getAsJsonObject();
JsonElement results = root.get("result");
Post[] posts = gson.fromJson(results, Post[].class);