Java HttP Post方法不工作

我试着用这种方法，我也试着取消诽谤，但都是徒劳的。请帮帮我。我的andriod studio上没有显示任何HTTPClient库。我们将不胜感激

 public String getHttpPost(String url,ContentValues) {
        StringBuilder str = new StringBuilder();

        HttpClient client = new DefaultHttpClient();
        HttpPost httpPost = new HttpPost(url);

        try {
            httpPost.setEntity(new UrlEncodedFormEntity(params));
            HttpResponse response = client.execute(httpPost);
            StatusLine statusLine = response.getStatusLine();
            int statusCode = statusLine.getStatusCode();
            if (statusCode == 200) { // Status OK
                HttpEntity entity = response.getEntity();
                InputStream content = entity.getContent();
                BufferedReader reader = new BufferedReader(new InputStreamReader(content));
                String line;
                while ((line = reader.readLine()) != null) {
                    str.append(line);
                }
            } else {
                Log.e("Log", "Failed to download result..");
            }
        } catch (ClientProtocolException e) {
            e.printStackTrace();
        } catch (IOException e) {
            e.printStackTrace();
        }
        return str.toString();
    }

---

哦!！您仍然在使用HttpClient。您可以使用HttpURLConnection、Volley等。HttpClient类现在已被弃用。还要在gradle文件中添加Internet权限和依赖项

 HttpURLConnection urlConnection = null;
                try {
                    URL urlToRequest = new URL(_url);
                    urlConnection = (HttpURLConnection) urlToRequest.openConnection();
                    urlConnection.setConnectTimeout(30000);
                    urlConnection.setReadTimeout(30000);
                    urlConnection.setDoOutput(true);
                    urlConnection.setDoInput(true);
                    urlConnection.setRequestProperty("Content-Type", "application/json");
                    urlConnection.setRequestProperty("Accept", "application/json");

                    if (_authenticationKey != null) {
                        urlConnection.setRequestProperty(_authenticationKey, _authenticationValue);
                    }
                    if (_jsonPacket != null) {
                        OutputStreamWriter wr = new OutputStreamWriter(urlConnection.getOutputStream());
                        wr.write(_jsonPacket);
                        wr.flush();
                    }

                    int statusCode = urlConnection.getResponseCode();

                    JSONObject job;
                    if (statusCode != HttpURLConnection.HTTP_OK) {
                        InputStream in = new BufferedInputStream(urlConnection.getErrorStream());
                        String responseString = getResponseString(in);
                        if (isJSONValid(responseString)) {
                            job = new JSONObject(responseString);
                            return new PostingResult(job, Constants.IntegerConstants.failureFromWebService, "");
                        } else {
                            return new PostingResult(null, statusCode, Constants.StringConstants.serverCommunicationFailed + "Response code = " + statusCode);
                        }

                    } else {
                        InputStream in = new BufferedInputStream(urlConnection.getInputStream());
                        String responseString = getResponseString(in);
                        if (isJSONValid(responseString)) {
                            job = new JSONObject(responseString);
                            return new PostingResult(job, Constants.IntegerConstants.success, "");
                        } else {
                            return new PostingResult(null, statusCode, Constants.StringConstants.serverCommunicationFailed + Constants.StringConstants.serverReadingResponseFailed);
                        }
                    }

您可以使用“截击”库进行网络呼叫

例如

在build.gradle（模块：app）中添加此行

编译'com.mcxiaoke.volley:library:1.0.19'

当您拨打网络电话时，您需要互联网许可。因此，在Manifest.xml中添加Internet权限行

现在，您需要在类中编写一个小方法，在该方法中，您需要进行网络调用并向其传递Hashmap。Hashmap包含所有post参数

private void getJSONResponse(HashMap<String, String> map, String url) {
        pd.show();
        JsonObjectRequest request = new JsonObjectRequest(Request.Method.POST, url, new JSONObject(map), new Response.Listener<JSONObject>() {
            @Override
            public void onResponse(JSONObject response) {
                Log.d("Mayur", "Response : " + response);
                //tv_res.setText(response.toString());
                //pd.dismiss();
            }
        }, new Response.ErrorListener() {
            @Override
            public void onErrorResponse(VolleyError error) {
                Toast.makeText(MainActivity.this, "Error Occured", Toast.LENGTH_SHORT).show();
                //tv_res.setText("ERROR");
                //pd.dismiss();
            }
        });
request.setRetryPolicy(new DefaultRetryPolicy(20000,DefaultRetryPolicy.DEFAULT_MAX_RETRIES,DefaultRetryPolicy.DEFAULT_BACKOFF_MULT));Volley.newRequestQueue(this).add(request);}

private void getJSONResponse（HashMap映射，字符串url）{
pd.show（）；
JsonObjectRequest=新的JsonObjectRequest（request.Method.POST、url、新的JSONObject（map）、新的Response.Listener（）{
@凌驾
公共void onResponse（JSONObject响应）{
日志d（“Mayur”，“响应：”+响应）；
//tv_res.setText（response.toString（））；
//pd.解散（）；
}
}，new Response.ErrorListener（）{
@凌驾
公共无效onErrorResponse（截击错误）{
Toast.makeText（MainActivity.this，“发生错误”，Toast.LENGTH_SHORT.show（）；
//tv_res.setText（“错误”）；
//pd.解散（）；
}
});
request.setRetryPolicy（新的DefaultRetryPolicy（20000，DefaultRetryPolicy.DEFAULT\u MAX\u RETRIES，DefaultRetryPolicy.DEFAULT\u BACKOFF\u MULT））；Volley.newRequestQueue（this）.add（request）；}

现在，在onCreate方法或任何其他方法中，只需创建post参数的Hashmap，并将其与post url一起传递给此方法

例如

HashMap map=newhashmap（）；
地图放置（“fname”、“Mayur”）；
地图放置（“lname”、“Thakur”）；
getJSONResponse（map，）；

您是否在gradle文件中添加了依赖项？您是否在AndroidManifeat.xml中添加了Internet权限？您是否希望使用其他方法进行网络调用，例如，使用库（如volley或Reformation）？是的，我添加了所有我添加了Internet权限，还添加了依赖项

HashMap<String, String> map = new HashMap<String, String>();
        map.put("fname", "Mayur");
        map.put("lname", "Thakur");
getJSONResponse(map,<your url>);