安卓 |向服务器发送“POST” JSON 数据

Question

我使用此代码使用 android 将发布数据发送到服务器。谁能给我任何想法或您的示例如何将 POST 或 GET json 数据发送到服务器 TOMCAT ..！ 步骤提示：

1. 创建 HttpClient
2. 向给定的 URL 发出 POST 请求
3. 构建 jsonObject
4. 将 JSONObject 转换为 JSON 到字符串
5. 将 json 设置为 StringEntity
6. 设置 httpPost 实体
7. 设置一些标头来通知服务器内容的类型
8. 对给定的 URL 执行 POST 请求
9. 作为输入流接收响应
10. 将输入流转换为字符串

11. 返回结果

    private class HttpAsyncTask extends AsyncTask<String, Void, String> {
    
            @Override
            protected String doInBackground(String... urls) {
    
            person = new Person();
            person.setName(etName.getText().toString());
            person.setCountry(etCountry.getText().toString());
            person.setTwitter(etTwitter.getText().toString());
    
            return POST(urls[0],person);
        }
        // onPostExecute displays the results of the AsyncTask.
        @Override
        protected void onPostExecute(String result) {
            Toast.makeText(getBaseContext(), "Data Sent!", Toast.LENGTH_LONG).show();
       }
    }
    

Answer 1

您正在使用 HttpClient。实际上，Android 弃用了 HttpClient 的 HttpClient，您需要“HttpURLConnection”进行 POST 请求检查这里的示例之一：here

更新：

您需要为示例代码添加以下两行以满足您的要求。

conn.addRequestProperty("Accept", "application/json");
conn.addRequestProperty("Content-Type", "application/json");

在给定的示例代码中：

conn.setDoOutput(true);
//Add the following line to the given sample
===============> updated for JSON POST <========================= 
conn.addRequestProperty("Accept", "application/json");
conn.addRequestProperty("Content-Type", "application/json");
===============> updated for JSON POST <========================= 
List<NameValuePair> params = new ArrayList<NameValuePair>();
params.add(new BasicNameValuePair("firstParam", paramValue1));
params.add(new BasicNameValuePair("secondParam", paramValue2));
params.add(new BasicNameValuePair("thirdParam", paramValue3));

Answer 2

如果你需要获取数据试试这个...

try{
    URL url = new URL("http://www.youraddresheredude.com/andthefile");
    //Open the connection here, and remember to close it when job its done.
    URLConnection conn = url.openConnection();
    conn.setRequestProperty("Content-Type", "application/json; charset=UTF-8");
    conn.setDoOutput(true);

    OutputStreamWriter wr = new OutputStreamWriter(conn.getOutputStream());
    //theJSONYouWantToSend should be the JSONObject as String
    wr.write(convertStandardJSONString(theJSONYouWantToSend));  //<--- sending data.

    wr.flush();

    //  Here you read any answer from server.
    BufferedReader serverAnswer = new BufferedReader(new InputStreamReader(conn.getInputStream()));
    String line;
    while ((line = serverAnswer.readLine()) != null) {

        System.out.println("LINE: " + line); //<--If any response from server
        //use it as you need, if server send something back you will get it here.
    }

    wr.close();
    serverAnswer.close();

} catch (Exception e) {
    Log.e("Cuack", "Something its wrong");
}

Answer 3

public class JSONParser {

static InputStream is = null;
static JSONObject jObj = null;
static String json = "";
static String responseString;

// constructor
public JSONParser() {

}

// function get json from url
// by making HTTP POST or GET mehtod
public static JSONObject makeHttpRequest(String url, String method,
                                         List<NameValuePair> params) {

    // Making HTTP request
    Log.d("json class", url + "," + method + "," + params.toString());
    try {

        // check for request method
        if (method == "POST") {
            // request method is POST
            // defaultHttpClient
            Log.d("json class", "post method");
            DefaultHttpClient httpClient = new DefaultHttpClient();
            HttpPost httpPost = new HttpPost(url);
            Log.d("json class", "HttpPost" + httpPost);
            httpPost.setEntity(new UrlEncodedFormEntity(params));
            Log.d("json class", "setentity");
            HttpResponse httpResponse = httpClient.execute(httpPost);

            ByteArrayOutputStream out = new ByteArrayOutputStream();
            int responce_code = httpResponse.getStatusLine()
                    .getStatusCode();
            Log.d("responce code", "response method");
            Log.d("responce code", "" + responce_code);
            StatusLine statusLine = httpResponse.getStatusLine();

            if (statusLine.getStatusCode() == HttpStatus.SC_OK) {
                Log.i("RESPONSE", "6");
                /*
                 * httpResponse.getEntity().writeTo(out); out.close();
                 * String responseString = out.toString(); Log.i("RESPONSE",
                 * ""+responseString);
                 */
                // ..more logic
            } else {
                Log.d("RESPONSE", "null pointer exception");
                // Closes the connection.
                httpResponse.getEntity().getContent().close();
                throw new IOException(statusLine.getReasonPhrase());
            }

            HttpEntity httpEntity = httpResponse.getEntity();
            is = httpEntity.getContent();

        } else if (method == "GET") {
            // request method is GET
            DefaultHttpClient httpClient = new DefaultHttpClient();
            String paramString = URLEncodedUtils.format(params, "utf-8");
            url += "?" + paramString;
            Log.i("url", url);
            HttpGet httpGet = new HttpGet(url);
            ByteArrayOutputStream out = new ByteArrayOutputStream();
            HttpResponse httpResponse = httpClient.execute(httpGet);
            int responce_code = httpResponse.getStatusLine()
                    .getStatusCode();
            Log.d("responce code", "response method");
            Log.d("responce code", "" + responce_code);

            StatusLine statusLine = httpResponse.getStatusLine();

            if (statusLine.getStatusCode() == HttpStatus.SC_OK) {

                Log.d("RESPONSE", "6");
                httpResponse.getEntity().writeTo(out);
                Log.d("RESPONSE", "7");
                out.close();
                Log.d("RESPONSE", "8");
                responseString = out.toString();
                Log.d("RESPONSE", "9");
                Log.i("RESPONSE", "" + responseString);
                // ..more logic
            } else {
                Log.d("RESPONSE", "null pointer exception");
                // Closes the connection.
                httpResponse.getEntity().getContent().close();
                throw new IOException(statusLine.getReasonPhrase());
            }
            /*
             * HttpEntity httpEntity = httpResponse.getEntity(); is =
             * httpEntity.getContent();
             */
        }
    } catch (UnsupportedEncodingException e) {
        e.printStackTrace();
    } catch (ClientProtocolException e) {
        e.printStackTrace();
    } catch (IOException e) {
        e.printStackTrace();
    }
    try {
        /*
         * BufferedReader reader = new BufferedReader(new InputStreamReader(
         * is, "iso-8859-1"), 8); StringBuilder sb = new StringBuilder();
         * String line = null; while ((line = reader.readLine()) != null) {
         * sb.append(line + "\n"); } is.close();
         */
        json = responseString.toString();
    } catch (Exception e) {
        Log.e("Buffer Error", "Error converting result " + e.toString());
    }
    // try parse the string to a JSON object
    try {
        jObj = new JSONObject(json);
    } catch (JSONException e) {

        Log.e("JSON Parser", "Error parsing data " + e.toString());
    }
    // return JSON String
    return jObj;
}

}