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How do I make a call OK HttpRequest post from an isolated class using async?

I was using this in another place as async but I wanted to refactor to make it reusable, how can I reorganize the code in order to work as a consumable class?. It doesn't work if it's not async and the ip of the backend is well defined so it's not that. Any ideas?
public class HTTPRequestManager {
public static JSONArray fetchData(){
return null;
}
public static String postData(Context context, String url, String JSONData) {
return null;
}
/* #Override
protected Integer doInBackground(String... strings) {
try {
//1.create client Object
OkHttpClient client = new OkHttpClient();
//2.Define request being sent to server
RequestBody postData = RequestBody.create(MediaType.parse("application/json; charset=utf-8"), JSONData);
Request request = new Request.Builder()
.url(context.getResources().getString(R.string.backend_base_url) + url)
.post(postData)
.build();
//3.Transport the request and wait for response to process next
Response response = client.newCall(request).execute();
String resultData = response.body().string();
if (resultData.equals("OK")) {
} else {
//post failed
return "FAILED";
}
return resultData;
} catch (Exception e) {
Log.d("API_CONNECTION_ERROR", "Couldn't connect to the API");
return "API_CONNECTION_ERROR";
}
}*/
}
I used to have this annonymous class embeeded in another class and it works(it's a get request) but the problem is that it's not reusable in that way:
public class AsyncHttpTask extends AsyncTask<String, Void, Integer> {
URL url = null;
#Override
protected void onPreExecute() {
getActivity().setProgressBarIndeterminateVisibility(true);
}
#Override
protected Integer doInBackground(String... params) {
Integer result = 0;
HttpURLConnection urlConnection;
try {
url = new URL (getResources().getString(R.string.backend_base_url) +
"api/flrcks/user/id/0/latitude/3000/longitude/300/within/9999999999999999999999999");
urlConnection = (HttpURLConnection) url.openConnection();
int statusCode = urlConnection.getResponseCode();
// 200 represents HTTP OK
if (statusCode == 200) {
BufferedReader r = new BufferedReader(new InputStreamReader(urlConnection.getInputStream()));
StringBuilder response = new StringBuilder();
String line;
while ((line = r.readLine()) != null) {
response.append(line);
}
parseResult(response.toString());
result = 1; // Successful
} else {
result = 0; //"Failed to fetch data!";
}
} catch (Exception e) {
Log.d(TAG, e.getLocalizedMessage());
}
return result; //"Failed to fetch data!";
}
#Override
protected void onPostExecute(Integer result) {
// Download complete. Let us update UI
progressBar.setVisibility(View.GONE);
if (result == 1) {
adapter = new MyRecyclerAdapter_Nearby(getActivity(), feedsList);
mRecyclerView.setAdapter(adapter);
checkAdapterIsEmpty();
} else {
Toast.makeText(getActivity(), "Failed to fetch data!", Toast.LENGTH_SHORT).show();
t.setVisibility(View.VISIBLE);
}
}
private void parseResult(String result) {
try {
JSONObject response = new JSONObject(result);
JSONArray posts = response.getJSONArray("rows");
feedsList = new ArrayList<>();
JSONArray members;
for (int i = 0; i < posts.length(); i++) {
memberList = new ArrayList<>();
final JSONObject post = posts.optJSONObject(i);
members=post.getJSONArray("members");
final FeedItem item = new FeedItem();
//for (int i = 0; i < posts.length(); i++) {
//JSONObject post = posts.optJSONObject(i);
//FeedItem item = new FeedItem();
item.setId(post.optString("id"));
item.setTitle(post.optString("name"));
item.setDescription(post.optString("description"));
item.setPrivacy(post.optString("privacy_mode_description"));
item.setInitial_date(post.optString("initial_date"));
item.setThumbnail(post.optString("thumbnail"));
item.setColor_hex(post.optString("color_hex"));
item.setTag(post.optString("tag"));
item.setDistance(post.optInt("st_distance"));
//item.setThumbnail(post.optString("thumbnail"));
for(int k=0; k <members.length();k++)
{
MemberItem memberItem = new MemberItem();
JSONObject member = members.optJSONObject(k);
memberItem.setName(member.optString("name"));
memberItem.setUsername(member.optString("username"));
memberItem.setProfile_pic(member.optString("profile_pic"));
memberItem.setIs_moderator(member.optBoolean("is_moderator"));
memberItem.setFacebookId(member.optString("facebook_id"));
memberList.add(memberItem);
}
item.setMemberList(memberList);
feedsList.add(item);
}
}
catch (JSONException e) {
e.printStackTrace();
}
}
}
What changes do I need to make to put it in an isolated file to be consumed by the whole app like for example in a file called OkHTTPRequests.class???

Create an interface
public interface OnWebResponseListener {
void onWebResponse(CommonUtilities.services service, String result);
}
create a public enum for identifying service. in my case i created a CommonUtilities java where i declared
public enum services {
LOGIN
}
Your Common File
public class CallAddr extends AsyncTask<String, Void, String> {
CommonUtilities.services service;
OnWebResponseListener onWebResponseListener;
String url;
FormBody.Builder body;
Request request;
OkHttpClient client;
final static String TAG = "CallAddr";
public CallAddr(Map<String, String> data, CommonUtilities.services service, OnWebResponseListener onWebResponseListener, String url) {
this.service = service;
this.onWebResponseListener = onWebResponseListener;
this.url = url;
body = new FormBody.Builder();
for (String key : data.keySet()) {
body.add(key, data.get(key));
}
client = new OkHttpClient();
}
#Override
protected String doInBackground(String... strings) {
String result = "";
request = new Request.Builder().url(url).post(body.build()).build();
try {
Response response = client.newCall(request).execute();
result = response.body().string();
} catch (Exception e) {
Log.e(TAG,Log.getStackTraceString(e));
}
return result;
}
#Override
protected void onPostExecute(String s) {
super.onPostExecute(s);
if (onWebResponseListener != null) {
onWebResponseListener.onWebResponse(service, s);
}
}
}

JSON parse error in php that produced in by jsonSerialize()

I use below code to produce JSON string and parse it in php. I create an instace of this class and call setData method
//#PART1
String s = "{\"Category\":";
List<CategoryModel> pmo = new ArrayList<CategoryModel>();
pmo = CategoryModule.getAllRecords(c);
s += new JSONSerializer().serialize(pmo);
s += ",\"Data\":";
//#PART2
List<DataModel> amo = new ArrayList<DataModel>();
amo = DataModule.getAllRecords(c);
s += new JSONSerializer().serialize(amo);
s += "}";
I decode the result by below code
$categories = json_decode($data)->{'Category'};
$datas = json_decode($data)->{'Data'};
$username = "kkk";
foreach($categories as $category){
$id = $category->{'id'};
$name = $category->{'name'};
$sql = "INSERT INTO category (id,name,username) VALUES ('$id','$name','$username')";
$link->query($sql);
}
foreach($datas as $data){
$id = $data->{'id'};
$text = $data->{'text'};
$date = $data->{'date'};
$sql = "INSERT INTO data (id,text,date,username) VALUES ('$id','$name','$date','$username')";
$link->query($sql);
}
When I just use #PART1 to produce json string in the php code the decoding occurs in success. But when I add #PART2 to JSON string no one of them decodes successfully. I guess the problem can be from java code.
Please guide me
JSON result is http://aiga.ir/webservice/datastore/a.txt
I use this code for sending data
package ir.aiga.apps.network;
public class WebServiceComm extends AsyncTask<String, Void, Void> {
// Required initialization
private String Content;
private String Error = null;
private ProgressDialog Dialog;
private String data ="";
private boolean visible=true;
private InterFace doInPreExecute=new InterFace() {
#Override
public void doSomething() {
// TODO Auto-generated method stub
}
#Override
public void getResult(String output) {
// TODO Auto-generated method stub
}
#Override
public void getJSONArray(JSONArray array) {
// TODO Auto-generated method stub
}
};
private InterFace doInPostExecute=new InterFace() {
#Override
public void doSomething() {
// TODO Auto-generated method stub
}
#Override
public void getResult(String output) {
// TODO Auto-generated method stub
}
#Override
public void getJSONArray(JSONArray array) {
// TODO Auto-generated method stub
}
};
public WebServiceComm(Context context,String title,String text){
try {
data +="&" + URLEncoder.encode("data", "UTF-8") + "=";
} catch (UnsupportedEncodingException e) {
// TODO Auto-generated catch block
e.printStackTrace();
}
Dialog=new ProgressDialog(context,ProgressDialog.STYLE_SPINNER);
Dialog.setTitle(title);
Dialog.setMessage(text);
}
public WebServiceComm(){
try {
data +="&" + URLEncoder.encode("data", "UTF-8") + "=";
} catch (UnsupportedEncodingException e) {
// TODO Auto-generated catch block
e.printStackTrace();
}
}
public void setData(String data){
this.data+=data;
}
protected void onPreExecute() {
// NOTE: You can call UI Element here.
if(visible)
Dialog.show();
}
// Call after onPreExecute method
protected Void doInBackground(String... urls) {
/************ Make Post Call To Web Server ***********/
BufferedReader reader=null;
// Send data
try
{
// Defined URL where to send data
URL url = new URL(urls[0]);
// Send POST data request
URLConnection conn = url.openConnection();
conn.setDoOutput(true);
OutputStreamWriter wr = new OutputStreamWriter(conn.getOutputStream());
wr.write( data );
wr.flush();
// Get the server response
reader = new BufferedReader(new InputStreamReader(conn.getInputStream()));
StringBuilder sb = new StringBuilder();
String line = null;
// Read Server Response
while((line = reader.readLine()) != null)
{
// Append server response in string
sb.append(line + "");
}
// Append Server Response To Content String
Content = sb.toString();
}
catch(Exception ex)
{
Error = ex.getMessage();
ex.printStackTrace();
}
finally
{
try
{
reader.close();
}
catch(Exception ex) {
ex.printStackTrace();
}
}
/*****************************************************/
return null;
}
protected void onPostExecute(Void unused) {
// NOTE: You can call UI Element here.
if (Error != null) {
} else {
// Show Response Json On Screen (activity)
/****************** Start Parse Response JSON Data *************/
JSONObject jsonResponse;
try {
/****** Creates a new JSONObject with name/value mappings from the JSON string. ********/
jsonResponse = new JSONObject(Content);
/***** Returns the value mapped by name if it exists and is a JSONArray. ***/
/******* Returns null otherwise. *******/
JSONArray jsonMainNode = jsonResponse.optJSONArray("Android");
doInPostExecute.getJSONArray(jsonMainNode);
doInPostExecute.doSomething();
if(visible)
Dialog.dismiss();
} catch (Exception e) {
e.printStackTrace();
}
}
}
/**
* #return the doInPreExecute
*/
public InterFace getDoInPreExecute() {
return doInPreExecute;
}
/**
* #param doInPreExecute the doInPreExecute to set
*/
public void setDoInPreExecute(InterFace doInPreExecute) {
this.doInPreExecute = doInPreExecute;
}
/**
* #return the doInPostExecute
*/
public InterFace getDoInPostExecute() {
return doInPostExecute;
}
/**
* #param doInPostExecute the doInPostExecute to set
*/
public void setDoInPostExecute(InterFace doInPostExecute) {
this.doInPostExecute = doInPostExecute;
}
/**
* #return the visible
*/
public boolean isVisible() {
return visible;
}
/**
* #param visible the visible to set
*/
public void setVisible(boolean visible) {
this.visible = visible;
}
}

please try to use this code for sending and receiving JSON with utf-8 encoding:
try {
URL url = new URL("your url");
HttpURLConnection conn = (HttpURLConnection) url.openConnection();
conn.setDoOutput(true);
OutputStreamWriter writer = new OutputStreamWriter(
conn.getOutputStream(), "UTF-8");
String request = "your json";
writer.write(request);
writer.flush();
System.out.println("Code:" + conn.getResponseCode());
System.out.println("mess:" + conn.getResponseMessage());
String response = "";
BufferedReader reader = new BufferedReader(new InputStreamReader(
conn.getInputStream(), "UTF-8"));
String line;
while ((line = reader.readLine()) != null) {
response += line;
}
System.out.println(new String(response.getBytes(), "UTF8"));
writer.close();
reader.close();
} catch (MalformedURLException e) {
e.printStackTrace();
} catch (IOException e) {
e.printStackTrace();
}

It's very bad to manually build JSON manually.
Using a JSON Mapper library
public class MyCustomModel {
public List<CategoryModel> Category;
public List<DataModel> Data;
public class CategoryModel{
//code here
}
public class DataModel{
//code here
}
}
Then use it GSON to serialize that object into JSON
MyCustomModel customModel = new MyCustomModel();
//populate object
//......
Gson gson = new Gson();
String json = gson.toJson(customModel);
Using standard library
JSONArray categoryArr = new JSONArray();
List<CategoryModel> categories = CategoryModule.getAllRecords(c);
for (CategoryModel category : categories) {
JSONObject categoryObj = new JSONObject();
categoryObj.put("class", category.getClass());
categoryObj.put("id", category.getId());
categoryObj.put("name", category.getName());
categoryArr.put(categoryObj);
}
Then do the same with the other list then combine both array
JSONObject jObject = new JSONObject();
jObject.put("Category", categoryArr);
jObject.put("Data", dataArr);

Multiple if else statement with parameter in doGet() servlet

I am having some problem when trying to execute different method in servlet doGet(). So when my button on click, it will pass along the eventID:
viewDtlEventBtn.setOnClickListener(new OnClickListener(){
public void onClick(View v){
Intent eventDtlIntent = new Intent(context, EventDetail.class);
eventDtlIntent.putExtra("eventID", eventIDTV.getText());
startActivity(eventDtlIntent);
}
});
Then in my EventDetail class, I am executing the method in AsyncTask class:
#Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.event_detail);
context = this;
Bundle extras = getIntent().getExtras();
if (extras != null) {
eventID = extras.getString("eventID");
}
eventModel.setEventID(eventID);
new GetEventDetailAsyncTask(context).execute(eventModel);
}
And in my AsyncTask class, I am calling the method in my controller which retrieving the JSON returned from servlet:
#Override
protected Double doInBackground(Event... params) {
try {
eventCtrl.getEventDetailByID(params[0]);
} catch (JSONException e) {
e.printStackTrace();
}
return null;
}
And in my controller class:
public Event getEventDetailByID(Event event) throws JSONException {
Event eventModel = new Event();
String page;
JSONArray jsonArray;
String eventID = event.getEventID();
try {
HttpClient client = new DefaultHttpClient();
HttpGet request = new HttpGet(ENeighbourhoodActivity.URL
+ "?getEventDetailByID&eventID=" + eventID +"");
HttpResponse response = client.execute(request);
HttpEntity entity = response.getEntity();
String responseString = EntityUtils.toString(entity, "UTF-8");
page = "{\'EventDetail\':" + responseString + "}";
try {
JSONObject jsonObject = new JSONObject(page);
jsonArray = jsonObject.getJSONArray("EventDetail");
int length = jsonArray.length();
for (int i = 0; i < length; i++) {
JSONObject attribute = jsonArray.getJSONObject(i);
String eventName = attribute.getString("eventName");
eventModel.setEventName(eventName);
}
} catch (JSONException e) {
e.printStackTrace();
}
} catch (IOException e) {
e.printStackTrace();
}
return event;
}
And basically from here, I am accessing the servlet. And in my doGet() in serlvet class:
protected void doGet(HttpServletRequest request,
HttpServletResponse response) throws ServletException, IOException {
JSONArray jsonArray = new JSONArray();
PrintWriter out = response.getWriter();
if (request.getParameter("getAllEvent") != null) {
}
catch (JSONException je) {
System.out.println(je.getMessage());
} catch (Exception exc) {
System.out.println(exc.getMessage());
}
out.println(jsonArray.toString());
}
}
I already have one if statement for some other methods. I wonder how should I pass the getEventDetailByID and the eventID parameter into servlet so that it knows which method to runs.
Thanks in advance.

Here is a example of how you can get the eventID value.
//gets value from getEventDetailByID parameter.
String detail = request.getParameter("getEventDetailByID");
if (detail != null && !detail.equals("")) {
int eventId = Integer.parseInt(request.getParameter("eventID"));
//get event detail by id with id
//e.g resultObject = myMethod(detail, eventId);
}
Update 1:
A better way of doing what is required:
String action = request.getParameter("action");
if (action.equalsIgnoreCase("GetById")) {
int eventId = Integer.parseInt(request.getParameter("eventID"));
//get event detail by id with id
//e.g resultObject = getById(eventId);
} else if (action.equalsIgnoreCase("GetAllEvents")) {
//Get all events
//e.g resultObject = GetAllEvents();
} else {
}
The URL usage:
to get event by id:
http://localhost:8080/WebService/EventDetailServlet?action=GetById&eventID=46
to get all event details
http://localhost:8080/WebService/EventDetailServlet?action=GetAllEvents

Syntax error on token "extends", throws expected - when implementing AsyncTask

I'm attempting to implement asynctask into my existing source code but I'm getting an error stating Syntax error on token "extends", throws expected
If I change
public void run() extends AsyncTask {
to
public void run() throws AsyncTask {
as eclipse seems to be asking me to do - I end up with:
No exception of type AsyncTask can be thrown; an exception type must be a subclass of Throwable
I simply need to figure out what I've done wrong in my asyncTask implementation.
JAVA
public class GetYouTubeUserVideosTask implements Runnable {
public static final String LIBRARY = "Library";
private final Handler replyTo;
private final String username;
public GetYouTubeUserVideosTask(Handler replyTo, String username) {
this.replyTo = replyTo;
this.username = username;
}
#Override
public void run() extends AsyncTask {
try {
HttpClient client = new DefaultHttpClient();
HttpUriRequest request = new HttpGet("https://gdata.youtube.com/feeds/api/videos?author="+username+"&v=2&alt=jsonc");
HttpResponse response = client.execute(request);
String jsonString = StreamUtils.convertToString(response.getEntity().getContent());
JSONObject json = new JSONObject(jsonString);
JSONArray jsonArray = json.getJSONObject("data").getJSONArray("items");
List<Video> videos = new ArrayList<Video>();
for (int i = 0; i < jsonArray.length(); i++) {
JSONObject jsonObject = jsonArray.getJSONObject(i);
String title = jsonObject.getString("title");
String url;
try {
url = jsonObject.getJSONObject("player").getString("mobile");
} catch (JSONException ignore) {
url = jsonObject.getJSONObject("player").getString("default");
}
String thumbUrl = jsonObject.getJSONObject("thumbnail").getString("sqDefault");
videos.add(new Video(title, url, thumbUrl));
}
Library lib = new Library(username, videos);
Bundle data = new Bundle();
data.putSerializable(LIBRARY, lib);
Message msg = Message.obtain();
msg.setData(data);
replyTo.sendMessage(msg);
} catch (ClientProtocolException e) {
Log.e("Feck", e);
} catch (IOException e) {
Log.e("Feck", e);
} catch (JSONException e) {
Log.e("Feck", e);
}
}
protected void onPostExecute(String result) {
// do something
}
protected void onPreExecute() {
// do something
}
protected void onProgressUpdate(String... text) {
// do something
}
}

Your asyncTask should be like the following, the class should extends AsyncTask not implements Runnable:
public final class GetYouTubeUserVideosTask extends AsyncTask<Void, Void, Void> {
public static final String LIBRARY = "Library";
private final Handler replyTo;
private final String username;
public GetYouTubeUserVideosTask(Handler replyTo, String username) {
this.replyTo = replyTo;
this.username = username;
}
/*
* #see android.os.AsyncTask#doInBackground(Params[])
*/
#Override
protected Void doInBackground(Void... arg0) {
try {
HttpClient client = new DefaultHttpClient();
HttpUriRequest request = new HttpGet("https://gdata.youtube.com/feeds/api/videos?author="+username+"&v=2&alt=jsonc");
HttpResponse response = client.execute(request);
String jsonString = StreamUtils.convertToString(response.getEntity().getContent());
JSONObject json = new JSONObject(jsonString);
JSONArray jsonArray = json.getJSONObject("data").getJSONArray("items");
List<Video> videos = new ArrayList<Video>();
for (int i = 0; i < jsonArray.length(); i++) {
JSONObject jsonObject = jsonArray.getJSONObject(i);
String title = jsonObject.getString("title");
String url;
try {
url = jsonObject.getJSONObject("player").getString("mobile");
} catch (JSONException ignore) {
url = jsonObject.getJSONObject("player").getString("default");
}
String thumbUrl = jsonObject.getJSONObject("thumbnail").getString("sqDefault");
videos.add(new Video(title, url, thumbUrl));
}
Library lib = new Library(username, videos);
Bundle data = new Bundle();
data.putSerializable(LIBRARY, lib);
Message msg = Message.obtain();
msg.setData(data);
replyTo.sendMessage(msg);
} catch (ClientProtocolException e) {
Log.e("Feck", e);
} catch (IOException e) {
Log.e("Feck", e);
} catch (JSONException e) {
Log.e("Feck", e);
}
return null;
}
/*
* #see android.os.AsyncTask#onPostExecute(java.lang.Object)
*/
#Override
protected void onPostExecute(Void result) {
}
}

Reflection - can't call java method from JSON-RPC request

I want to call a method based on JSON-RPC request from a servlet I have code like this:
public void doPost(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {
response.setContentType("application/json");
ServletInputStream in = request.getInputStream();
PrintWriter out = response.getWriter();
String json_request = this.readStream(in);
Object id = null;
try {
JSONRPC2Request reqIn = JSONRPC2Request.parse(json_request);
id = reqIn.getID();
Object params = reqIn.getPositionalParams().toArray();
String method_name = reqIn.getMethod();
Service service = new Service();
Method[] methods = service.getClass().getMethods();
Method method = null;
// getMethod need class as second argument
for (int i=0; i<methods.length; ++i) {
if (methods[i].getName().equals(method_name)) {
method = methods[i];
break;
}
}
if (method != null) {
Object result = method.invoke(service, params);
JSONRPC2Response respOut = new JSONRPC2Response(result, id);
out.println(respOut);
} else {
out.println(JSONRPC2Error.METHOD_NOT_FOUND);
}
} catch (IllegalArgumentException e) {
out.println(new JSONRPC2Response(JSONRPC2Error.INVALID_PARAMS, id));
} catch (IllegalAccessException e) {
out.println(new JSONRPC2Response(JSONRPC2Error.INTERNAL_ERROR, id));
} catch (InvocationTargetException e) {
out.println(new JSONRPC2Response(JSONRPC2Error.INTERNAL_ERROR, id));
} catch (JSONRPC2ParseException e) {
out.println("{\"error\": \"Parse Error: " + e.getMessage() + "\"}");
}
}
I try to call method login from service class:
public class Service {
public String login(String username, String password) {
return "token";
}
}
I call it from javascript using jQuery:
var request = JSON.stringify({
method: "login",
params: ["foo", "Bar"],
id: 1,
jsonrpc: "2.0"
});
$.post('/app/rpc', request, function(res) { console.log(res); });
But I keep getting runtime IllegalArgumentException. What's wrong with my code? I also try to cast params to object with the same result.