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Parsing OkHttp in android?

textView = findViewById(R.id.textVieww);
String url = "https://zenquotes.io/api/random";
OkHttpClient client = new OkHttpClient();
Request request = new Request.Builder()
.url(url)
.build();
client.newCall(request).enqueue(new Callback() {
#Override
public void onFailure(Call call, IOException e) {
e.printStackTrace();
}
#Override
public void onResponse(Call call, Response response) throws IOException {
if (response.isSuccessful()) {
final String myResponse = response.body().string();
try {
JSONArray jsonarray = new JSONArray(myResponse);
for(int i=0; i<jsonarray.length(); i++) {
JSONObject obj = jsonarray.getJSONObject(i);
}
} catch (JSONException e) {
e.printStackTrace();
}
Quote.this.runOnUiThread(() ->
textView.setText(myResponse));
}
}
});
}
This is the part im stuck on i think im on the right track but not sure where to go from here im trying to get the "q" information from the returned url and the "a" information but it just outputs everything any suggestions?

What was your problem
Even when you parsed JSON string, you were still using the myResponse string in your textView.setText() method.
Continuing your code snippet
your code snippet is quite short, but i do think i can quite understand what you mean.
So let's say that we have Activity, which is called MainActivity and in that activity we have two views, one TextView called that has an id of tv_author_and_quote and one Button which has a xml id btn_request_quote.
The button has an OnClickListener which calls method requestForQuote().
Our onCreate + the variables of Button and TextView looks like this:
TextView tvAuthorAndQuote;
Button btnRequestQuote;
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
tvAuthorAndQuote = findViewById(R.id.tv_author_and_quote);
btnRequestQuote = findViewById(R.id.btn_request_quote);
btnRequestQuote.setOnClickListener(new View.OnClickListener() {
#Override
public void onClick(View v) {
requestForQuote();
}
});
}
And then we have a code itself for method requestForQuote():
public void requestForQuote() {
OkHttpClient client = new OkHttpClient();
Request request = new Request.Builder()
.url(URL)
.build();
client.newCall(request).enqueue(new Callback() {
#Override
public void onFailure(#NotNull Call call, #NotNull IOException e) {
e.printStackTrace();
}
#Override
public void onResponse(#NotNull Call call, #NotNull Response response) throws IOException {
if (response.isSuccessful()) {
final String myResponse = Objects.requireNonNull(response.body()).string();
String myFormattedQuote = "";
try {
JSONArray jsonarray = new JSONArray(myResponse);
for(int i=0; i<jsonarray.length(); i++) {
JSONObject obj = jsonarray.getJSONObject(i);
String quote = obj.getString("q");
String author = obj.getString("a");
Log.d(TAG, "onResponse: quote:" + quote);
Log.d(TAG, "onResponse: author:" + author);
myFormattedQuote = author + ": " + quote;
}
} catch (JSONException e) {
e.printStackTrace();
}
final String myFinalQuote = myFormattedQuote;
MainActivity.this.runOnUiThread(() -> {
if (!myFinalQuote.equals("")) {
tvAuthorAndQuote.setText(myFinalQuote);
} else {
tvAuthorAndQuote.setText(myResponse);
}
});
}
}
});
}
The code above basically uses your existing solution, but instead of setting the text of textView with myResponse string, it parses the json array and gets a quote and an author from it. Then it just logs it (just for testing purposes), then it constructs the string which gets displayed to the if there is any, otherwise it prints the response. That it is.
Using Gson library
import it into your gradle dependecies
implementation 'com.google.code.gson:gson:2.8.7'
Write short "holder" class called Quote
public class Quote {
public Quote() {
}
String q;
String a;
String h;
public String getQ() {
return q;
}
public void setQ(String q) {
this.q = q;
}
public String getA() {
return a;
}
public void setA(String a) {
this.a = a;
}
public String getH() {
return h;
}
public void setH(String h) {
this.h = h;
}
#NonNull
#NotNull
#Override
public String toString() {
return a + ": " + q;
}
}
Then the requestForQuote() method could look something like this:
public void requestForQuoteWithGson() {
OkHttpClient client = new OkHttpClient();
Request request = new Request.Builder()
.url(URL)
.build();
client.newCall(request).enqueue(new Callback() {
#Override
public void onFailure(#NotNull Call call, #NotNull IOException e) {
e.printStackTrace();
}
#Override
public void onResponse(#NotNull Call call, #NotNull Response response) throws IOException {
if (response.isSuccessful()) {
final String myResponse = Objects.requireNonNull(response.body()).string();
Type listType = new TypeToken<ArrayList<Quote>>(){}.getType();
List<Quote> yourClassList = new Gson().fromJson(myResponse, listType);
if (yourClassList != null && yourClassList.size() > 0) {
final Quote quote = yourClassList.get(0);
if (quote != null) {
myQuotes.add(quote);
MainActivity.this.runOnUiThread(() ->
tvAuthorAndQuote.setText(quote.toString())
);
}
}
}
}
});
}

Parsion JSON String into JSONOBJECT in android [duplicate]

This question already has answers here:
How do I parse JSON in Android? [duplicate]
(3 answers)
Using GSON to parse a JSON with dynamic "key" and "value" in android
(2 answers)
Closed 5 years ago.
This is my JsonResponse , and since its not in array i am facing some difficulties , can any one help me out ? in android
{
"errorno": "0",
"responsemsg": "Login Success.",
"busid": "1234",
"returnmobileno": "1234567890"
}

try this
try {
JSONObject lJsonObject = new JSONObject(response);
String errorno = lJsonObject .getString("errorno");
String responsemsg = lJsonObject .getString("responsemsg");
String busid = response.lJsonObject ("busid");
String returnmobileno = lJsonObject .getString("returnmobileno");
} catch (JSONException e) {
e.printStackTrace();
}

Try this,
try {
String errorno = response.getString("errorno");
String responsemsg = response.getString("responsemsg");
String busid = response.getString("busid");
String returnmobileno = response.getString("returnmobileno");
Log.d(TAG, "errorno:" + errorno+" responsemsg:"+responsemsg+" busid:"+busid+" returnmobileno:"+returnmobileno);
} catch (JSONException e) {
e.printStackTrace();
}

use below code to pass your strong
serverData = gson.fromJson(response, ServerData.class);
in build.gradle -> dependencies
// retrofit, gson
implementation 'com.google.code.gson:gson:2.8.2'
implementation 'com.squareup.retrofit2:retrofit:2.3.0'
implementation 'com.squareup.retrofit2:converter-gson:2.3.0'
public class ApiClient {
public static final String SERVER_BASE_URL = "http://example.com/abc/";
private static Retrofit retrofit = null;
public static Retrofit getClient() {
if (retrofit == null) {
retrofit = new Retrofit.Builder()
.baseUrl(SERVER_BASE_URL)
.addConverterFactory(GsonConverterFactory.create())
.build();
}
return retrofit;
}
}
public interface ApiInterface {
#POST("appServices/getData.php")
#FormUrlEncoded
Call<ResponseBody> getAllDataJSONFromServer(#Field("vcode") String vcode);
}
public class ServerData implements Parcelable {
public static final Creator<ServerData> CREATOR = new Creator<ServerData>() {
#Override
public ServerData createFromParcel(Parcel in) {
return new ServerData(in);
}
#Override
public ServerData[] newArray(int size) {
return new ServerData[size];
}
};
private static final int VERSION = 1;
#SerializedName("errorno")
private String errorno;
#SerializedName(responsemsg)
private String responsemsg;
#SerializedName("busid")
private String busid;
#SerializedName("returnmobileno")
private String returnmobileno;
private void readFromParcel(Parcel in) {
if (in.readInt() == VERSION) {
errorno = in.readString();
responsemsg = in.readString();
busid = in.readString();
returnmobileno = in.readString();
}
}
public void writeToParcel(Parcel parcel, int i) {
parcel.writeInt(VERSION);
parcel.writeString(errorno);
parcel.writeString(responsemsg);
parcel.writeString(busid);
parcel.writeString(returnmobileno);
}
#Override
public int describeContents() {
return 0;
}
public String getErrorno() {
return errorno;
}
public void setErrorno(String errorno) {
this.errorno = errorno;
}
public String getResponsemsg() {
return responsemsg;
}
public void setResponsemsg(String responsemsg) {
this.responsemsg = responsemsg;
}
public String getBusid() {
return busid;
}
public void setBusid(String busid) {
this.busid = busid;
}
public String getReturnmobileno() {
return returnmobileno;
}
public void setReturnmobileno(String returnmobileno) {
this.returnmobileno = returnmobileno;
}
}
ApiInterface apiService = ApiClient.getClient().create(ApiInterface.class);
// get and save all data from server
Call<ResponseBody> call = apiService.getAllDataJSONFromServer(local_vcode, local_cvcode, pckgName);
call.enqueue(new Callback<ResponseBody>() {
#SuppressWarnings("ConstantConditions")
#Override
public void onResponse(Call<ResponseBody> call, Response<ResponseBody> responsebody) {
try {
String response = responsebody.body().string();
serverData = gson.fromJson(response, ServerData.class); // this will fetch data to model class ServerData
if (serverData != null) {
// do the rest here...
String vcode = serverData.getVcode();
Log.e("~~~ vode = ", vcode);
}
} catch (Exception e) {
e.printStackTrace();
} finally {
progressDialog.dismiss();
}
}
#Override
public void onFailure(Call<ResponseBody> call, Throwable t) {
try {
t.printStackTrace();
progressDialog.dismiss();
} catch (Exception ignored) {
}
}
});

Gson deserializer support multiple types

I want to deserialize a JSON response but I'm not sure about the format. The format can vary in each case. For example the response contains a field named "error" which may be false (boolean) or an object that describes the error eg. "error": { "code": xxx , "description":"etc"}
How should I implement a class that covers both cases? Is there any way to do this?
Thanks

I would prefer using a TypeAdapter for your case:
private static class Error {
private boolean hasError;
private int code;
private String description;
}
private static class ErrorTypeAdapter extends TypeAdapter<Error> {
#Override
public Error read(JsonReader jsonReader) throws IOException {
Error response = null;
jsonReader.beginObject();
while (jsonReader.hasNext()) {
String currentJsonName = jsonReader.nextName();
if("error".equals(currentJsonName)) {
response = new Error();
try {
response.hasError = jsonReader.nextBoolean();
} catch (Exception e) {
response.hasError = true;
jsonReader.beginObject();
}
} else if("code".equals(currentJsonName)) {
response.code = jsonReader.nextInt();
} else if ("description".equals(currentJsonName)) {
response.description = jsonReader.nextString();
}
}
if(response.hasError) {
jsonReader.endObject();
}
jsonReader.endObject();
return response;
}
#Override
public void write(JsonWriter jsonWriter, Error response)
throws IOException {
jsonWriter.beginObject();
jsonWriter.name("hasError").value(response.hasError);
jsonWriter.name("code").value(response.code);
jsonWriter.name("description").value(response.description);
jsonWriter.endObject();
}
}
To test it you can use:
String val1 = "{\"error\": {\"code\": 1 , \"description\":\"etc\"}}";
String val2 = "{\"error\": false}";
final GsonBuilder gsonBuilder = new GsonBuilder();
gsonBuilder.registerTypeAdapter(Error.class, new ErrorTypeAdapter());
gsonBuilder.setPrettyPrinting();
final Gson gson = gsonBuilder.create();
gson.fromJson(val1, Error.class);
gson.fromJson(val2, Error.class);
You can read more about TypeAdapters here and also some great examples here.

playframework-2.3 Akka-Async interaction porting?

I have some old playframework 2.2 java webservice that interacts with akka, and now I should port them to playframework 2.3.
However, async has been deprecated and even after reading the doc about the async porting (http://www.playframework.com/documentation/2.3.x/JavaAsync) I wasn't able to understand how to apply it to my case (code below):
I must make the await for a timeout/akka server reply before starting the construction of my reply (ok()), otherwise I will block the thread.
I should make the actorselection async too.
I should make the akka server reply parsing/reply construction async too
I looked around and I wasn't able to find an example of such interactions, even in typesafe templates.
How could I do that?
/* playframework 2.2 code */
public class Resolve extends Controller {
private final static String RESOLVER_ACTOR = play.Play.application().configuration().getString("actor.resolve");
#CorsRest
#VerboseRest
#RequireAuthentication
#BodyParser.Of(BodyParser.Json.class)
public static Result getJsonTree() {
JsonNode json = request().body().asJson();
ProtoBufMessages.ResolveRequest msg;
ResolveRequestInput input;
try {
input = new ResolveRequestInput(json);
} catch (rest.exceptions.MalformedInputException mie) {
return badRequest(mie.getMessage());
}
msg = ((ProtoBufMessages.ResolveRequest)input.getMessage());
ActorSelection resolver = Akka.system().actorSelection(RESOLVER_ACTOR);
Timeout tim = new Timeout(Duration.create(4, "seconds"));
Future<Object> fut = Patterns.ask(resolver, input.getMessage(), tim);
return async (
F.Promise.wrap(fut).map(
new F.Function<Object, Result>() {
public Result apply(Object response) {
ProtoBufMessages.ResolveReply rsp = ((ProtoBufMessages.ResolveReply)response);
ResolveOutput output = new ResolveOutput(rsp);
return ok(output.getJsonReply());
}
}
)
);
}
}

I came out with the code below
public class Resolve extends Controller {
private final static String RESOLVER_ACTOR = play.Play.application().configuration().getString("actor.resolve");
private final static BrainProtoMessages.ResolveReply request_error = BrainProtoMessages.ResolveReply.newBuilder()
.setReturnCode(BResults.REQUEST_FAILED)
.build();
#CorsRest
#VerboseRest
#RequireAuthentication
#BodyParser.Of(BodyParser.Json.class)
public static Result resolve_map() {
final ResolveRequestInput input;
final F.Promise<ActorSelection> selected_target;
final F.Promise<Future<Object>> backend_request;
final F.Promise<BrainProtoMessages.ResolveReply> backend_reply;
final F.Promise<ObjectNode> decode_json;
final F.Promise<Result> ok_result;
final JsonNode json = request().body().asJson();
try {
input = new ResolveRequestInput(json);
} catch (rest.exceptions.MalformedInputException mie) {
return badRequest(mie.getMessage());
}
selected_target = F.Promise.promise(
new F.Function0<ActorSelection>() {
#Override
public ActorSelection apply() throws Throwable {
return Akka.system().actorSelection(RESOLVER_ACTOR);
}
}
);
backend_request =
selected_target.map(
new F.Function<ActorSelection, Future<Object>>() {
#Override
public Future<Object> apply(ActorSelection actorSelection) throws Throwable {
return Patterns.ask(actorSelection, input.getMessage(),new Timeout(Duration.create(4, "seconds")));
}
}
);
backend_reply = backend_request.map(
new F.Function<Future<Object>, BrainProtoMessages.ResolveReply>() {
#Override
public BrainProtoMessages.ResolveReply apply(Future<Object> akka_reply) throws Throwable {
try {
return (BrainProtoMessages.ResolveReply) Await.result(akka_reply, Duration.create(4, "seconds"));
}catch(Exception error)
{
return request_error;
}
}
}
);
decode_json = backend_reply.map(
new F.Function<BrainProtoMessages.ResolveReply, ObjectNode>() {
#Override
public ObjectNode apply(BrainProtoMessages.ResolveReply response) throws Throwable {
return new ResolveOutput(response).getJsonReply();
}
}
);
ok_result = decode_json.map(
new F.Function<ObjectNode, Result>() {
#Override
public Result apply(ObjectNode reply) {
return ok(reply);
}
}
);
try {
return ok_result.get(8000);
}catch(Exception error)
{
return internalServerError();
}
}
}

Need ideas on fixing RSS feed parsing

http://www.ibm.com/developerworks/opensource/library/x-android/
I am using the code here, specifically the AndroidSaxParser. The problem is, is that I get all 4 parts of the Message objects the same as the title. I've combed it over and over, but I can't find anything wrong with what I put together.
Any ideas on where to look?
Here is the code:
public class AndroidSaxFeedParser extends BaseFeedParser {
public AndroidSaxFeedParser(String feedUrl) {
super(feedUrl);
}
public List<Message> parse() {
final Message currentMessage = new Message();
RootElement root = new RootElement("rss");
final List<Message> messages = new ArrayList<Message>();
Element channel = root.getChild("channel");
Element item = channel.getChild(ITEM);
item.setEndElementListener(new EndElementListener(){
public void end() {
messages.add(currentMessage.copy());
}
});
item.getChild(TITLE).setEndTextElementListener(new EndTextElementListener(){
public void end(String body) {
currentMessage.setTitle(body);
}
});
item.getChild(LINK).setEndTextElementListener(new EndTextElementListener(){
public void end(String body) {
currentMessage.setLink(body);
}
});
item.getChild(DESCRIPTION).setEndTextElementListener(new EndTextElementListener(){
public void end(String body) {
currentMessage.setDescription(body);
}
});
item.getChild(PUB_DATE).setEndTextElementListener(new EndTextElementListener(){
public void end(String body) {
currentMessage.setDate(body);
}
});
try {
Xml.parse(this.getInputStream(), Xml.Encoding.UTF_8, root.getContentHandler());
} catch (Exception e) {
throw new RuntimeException(e);
}
return messages;
}
}
public abstract class BaseFeedParser implements FeedParser {
// names of the XML tags
static final String PUB_DATE = "pubDate";
static final String DESCRIPTION = "description";
static final String LINK = "link";
static final String TITLE = "title";
static final String ITEM = "item";
static final String CHANNEL = "channel";
final URL feedUrl;
protected BaseFeedParser(String feedUrl){
try {
this.feedUrl = new URL(feedUrl);
} catch (MalformedURLException e) {
throw new RuntimeException(e);
}
}
protected InputStream getInputStream() {
try {
return feedUrl.openConnection().getInputStream();
} catch (IOException e) {
throw new RuntimeException(e);
}
}
}