I have this json
https://maps.googleapis.com/maps/api/directions/json?origin=-22.8895625,-47.0714089&destination=-22.892376,-47.027553&key=
And I need deserialize it
But I get this error
Additional text encountered after finished reading JSON content: ,. Path '', line 8, position 4.
What I am doing:
public static async Task<List<Model.Localizacao>> GetDirectionsAsync(Localizacao locUser, Localizacao locLoja)
{
using (var client = new HttpClient())
{
try
{
List<Model.Localizacao> lstLoc = new List<Model.Localizacao>();
var json = await client.GetStringAsync("https://maps.googleapis.com/maps/api/directions/json?origin=" + locUser.latitude + "," + locUser.longitude + "&destination="+ locLoja.latitude+","+locLoja.longitude+"&key=" + GOOGLEMAPSKEY);
json = json.Substring(json.IndexOf('['));
json = json.Substring(0, json.LastIndexOf(']') + 1);
lstLoc = JsonConvert.DeserializeObject<List<Model.Localizacao>>(json);
return lstLoc;
}
catch (Exception ex)
{
Debug.WriteLine(ex.Message);
return null;
}
}
}
this is my class:
namespace neoFly_Montana.Model
{
class Localizacao
{
public double latitude { get; set; }
public double longitude { get; set; }
}
}
How can I solve that?
My key is the same for the maps of google
I believe the problem is in these lines:
json = json.Substring(json.IndexOf('['));
json = json.Substring(0, json.LastIndexOf(']') + 1);
This appears to set json to be all the text from the first [ to the last ]. That means that you're going to wind up with some malformed json.
geocoded_waypoints is an array, but so is routes, which means you're going to wind up with a String that looks like this:
[
{ "geocoder_status" : "OK" ... }
{ "geocoder_status" : "OK" ... }
], "routes": [
{ "bounds": { ... } ... }
]
That , "routes": [ will fail to parse.
Update
After some discussion in the comments, I think I'm at the end of the help I'm able to provide. I'm not familiar with C# or the particular JSON parsing library you're using.
However, I can offer some ideas as a starting point.
The JSON coming back from that Google call has a particular structure. I suspect you will have to create new model classes that match this structure. For example, the top-level object would have three fields, and might look like this in Java:
public class ApiResponse {
private List<Waypoint> geocoded_waypoints;
private List<Route> routes;
private String status;
}
Then you'd have to implement Waypoint and Route, again matching the structure of the Google response:
public class Waypoint {
private String geocoder_status;
private String place_id;
private List<String> types;
}
public class Route {
private Bounds bounds;
private String copyrights;
private List<Leg> legs;
private Polyline overview_polyline;
private String summary;
private List<String> warnings;
private List<String> waypoint_order;
}
And so on. Once you have a class to represent the top-level response as well as all the various sub-objects inside that response, you would probably be able to change this code:
List<Model.Localizacao> lstLoc = new List<Model.Localizacao>();
var json = await client.GetStringAsync("https://maps.googleapis.com/maps/api/directions/json?origin=" + locUser.latitude + "," + locUser.longitude + "&destination="+ locLoja.latitude+","+locLoja.longitude+"&key=" + GOOGLEMAPSKEY);
json = json.Substring(json.IndexOf('['));
json = json.Substring(0, json.LastIndexOf(']') + 1);
lstLoc = JsonConvert.DeserializeObject<List<Model.Localizacao>>(json);
return lstLoc;
to this:
var json = await client.GetStringAsync("https://maps.googleapis.com/maps/api/directions/json?origin=" + locUser.latitude + "," + locUser.longitude + "&destination="+ locLoja.latitude+","+locLoja.longitude+"&key=" + GOOGLEMAPSKEY);
return JsonConvert.DeserializeObject<ApiResponse>(json);
Related
In the past a manually created as list of data, which was stored locally in a database. Now I would like to parse those data and put them through import json option into firebase dbs, but what I get doesn't look like firebase generated json.
What I get is:
[
{
"id":"id_1",
"text":"some text"
},
{
"id":"id_2",
"text":"some text2"
},
...
]
what I want is something like this:
{
"id_1": {
"text":"some text",
"id":"id_1"
},
"id_2":{
"text":"some text2",
"id":"id_1"
},
...
}
my Card class
class Card{
private String id;
private String text;
}
retrieving data
//return list of card
List<Card> cards =myDatabase.retrieveData();
Gson gson = new Gson();
String data = gson.toJson(cards);
So how I can I achieve this (it looks to me) dynamically named properties for json that look like those generated by firebase ?
EDIT:
I found that gson has FieldNamingStrategy interface that can change names of fields. But it looks to me it's not dynamic as I want.
EDIT2
my temp fix was to just override toString()
#Override
public String toString() {
return "\""+id+"\": {" +
"\"text\":" + "\""+text+"\","+
"\"id\":" +"\""+ id +"\","+
"\"type\":"+ "\""+ type +"\""+
'}';
}
Your "temp fix" will store each object as a string not a object.
You need to serialize an object to get that data, not a list.
For example, using a Map
List<Card> cards = myDatabase.retrieveData();
Map<Map<String, Object>> fireMap = new TreeMap<>();
int i = 1;
for (Card c : cards) {
Map<String, Object> cardMap = new TreeMap<>();
cardMap.put("text", c.getText());
fireMap.put("id_" + (i++), cardMap);
}
Gson gson = new Gson();
String data = gson.toJson(fireMap);
I am calling web-services which can have 2 types of json object in response. Now sometimes i get key profile with type String and sometimes it may have same key with type 'ProfileSubObject'. So how to manage this case? Below are my two types of object. I am using Jackson library to parse json.
1.)
{
"data": [
{
"profession": "iOS Developer",
"thanks": {
"count": 5
},
"profile": "test"
}
]
}
2.)
{
"data": [
{
"profession": "iOS Developer",
"thanks": {
"count": 5
},
"profile": {
"val1":"test1",
"val2":"test2"
}
}
]
}
Key profile have 2 different type of object based on web-service call.
Following is my data class structure.
#JsonInclude(JsonInclude.Include.NON_NULL)
#JsonIgnoreProperties(ignoreUnknown = true)
public class DataObject {
#JsonProperty("profession")
private String profession;
#JsonProperty("profile")
private ProfileObject profile;
#JsonProperty("thanks")
private ThanksObject thanks;
public String getProfession() {
return profession;
}
public ThanksObject getThanks() {
return thanks;
}
public ProfileObject getProfile() {
return profile;
}
}
And Profile class is as per below.
public class ProfileObject {
ProfileObject(){
}
ProfileObject(ProfileSubObject profileSubObject){
this.profileSubObject= profileSubObject;
}
ProfileObject(String profile){
this.profile= profile;
}
private ProfileSubObject profileSubObject;
private String profile;
public ProfileSubObject getProfileSubObject() {
return profileSubObject;
}
}
Now when i parse my object, ProfileObject is always null. I want it to get parsed based on proifle key data type.
Anyone could help me with parsing?
In constructing the solution, I faced two problems:
the Json structure does not match a single DataObject
the original problem of deserializing same property into differnt types of Java objects.
The first problem I solved by constructing JavaType objects which tell Jackson the generic type of the collections involved. There are two such collections: a Map, consisting of a single entry with key "data" and value of List of DataObjects
The second problem, I solved with the Jackson feature of #JsonAnySetter which directs Jackson to call a single method for all properties it doesn't recognize. For this purpose, I added #JsonIgnore to the profile variable to make sure that Jackson indeed doesn't recognize it. Now Jackson calls the same method for the two input jsons
This is the new DataObject class:
#JsonInclude(JsonInclude.Include.NON_NULL)
#JsonIgnoreProperties(ignoreUnknown = true)
public class DataObject
{
#JsonProperty("profession")
public String profession;
#JsonIgnore // forcing jackson to not recognize this property
public ProfileObject profile;
#JsonProperty("thanks")
public ThanksObject thanks;
public String getProfession() { return profession; }
public void setProfession(String p) { profession = p; }
public ThanksObject getThanks() { return thanks; }
public void setThanks(ThanksObject t) { thanks = t; }
public ProfileObject getProfile() { return profile; }
public void setProfile(ProfileObject p) { profile = p; }
#JsonAnySetter
public void setProfileFromJson(String name, Object value)
{
// if value is single String, call appropriate ctor
if (value instanceof String) {
profile = new ProfileObject((String)value);
}
// if value is map, it must contain 'val1', 'val2' entries
if (value instanceof Map) {
ProfileSubObject profileSubObject =
new ProfileSubObject(((Map<String, String>)value).get("val1"), ((Map<String, String>)value).get("val2"));
profile = new ProfileObject(profileSubObject);
}
// error?
}
}
Here is my test method, which includes the java type construction I mentioned:
public static void main(String[] args)
{
try (Reader reader = new FileReader("C://Temp/xx2.json")) {
ObjectMapper mapper = new ObjectMapper();
// type of key of map is String
JavaType stringType = TypeFactory.defaultInstance().constructType(String.class);
// type of value of map is list of DataObjects
JavaType listOfDataObject = TypeFactory.defaultInstance().constructCollectionType(List.class, DataObject.class);
// finally, construct map type with key and value types
JavaType rootMap = TypeFactory.defaultInstance().constructMapType(HashMap.class, stringType, listOfDataObject);
Map<String ,List<DataObject>> m = mapper.readValue(reader, rootMap);
DataObject do1 = m.values()
// get first (only?) value in map (it is list)
.stream().findFirst().orElse(Collections.emptyList())
// get first (only?) item in list - it is the DataObject
.stream().findFirst().orElse(null);
System.out.println(do1.profile);
System.out.println(do1.profile.profile);
System.out.println(do1.profile.profileSubObject.val1 + " " + do1.profile.profileSubObject.val2);
} catch (Exception e) {
e.printStackTrace();
}
}
This may be of help in regards to parsing JSON, use a JsonReader. It does assume you are using RESTful webservice and have already gotten a HttpURLConnection and an InputStream from the connection.
https://developer.android.com/reference/android/util/JsonReader.html
Say I need to fill a Binary Search Tree with data obtained from Server. Say further that the data coming from server is a json array of nodes
"parts":[{"id":1,"name":"apple"},{"id":12,"name":"orange"},{"id":21,"name":"pen"},{"id":214,"name":"kite"}]//where each {} represents a node
How do I use GSon to read the array of Nodes into my BST?
If you recall a BST has two classes
public class BST{
private Note root;
}
public class Node{
String el;
Node left, right;
}
If BST is too hard, image something simpler
public class MyDataStructure{
private List<Part> partsList;
…
}
public class Part{
String el;
List<String> stuff;
}
How do I populate MyDataStructure with partsList using GSon on android? As a side note, I would rather help solving the MyDataStruction version of the problem.
ok.. you can use this as reference:
define a class pojo
and a Fruit(is the array/list/collection)
the pojo
class Pojo {
#Override
public String toString() {
return "Pojo [parts=" + parts + "]";
}
private List<Fruits> parts;
}
the fruit
class Fruits {
private int id;
private String name;
#Override
public String toString() {
return "[id=" + id + ", name=" + name + "]";
}
}
the implementation
String json = "{\"parts\": [{\"id\":1,\"name\":\"apple\"},{\"id\":2,\"name\":\"pear\"},{\"id\":3,\"name\":\"kiwi\"}]}";
Gson g = new Gson();
Pojo p = g.fromJson(json, Pojo.class);
System.out.println(p);
the MyDataStructure population
add to the pojo a setter getter so you can work with the list, add too setter and getter for the fruit class so you can get the id and the name..
so in the pojo object p you can do p.getList() and iterate over the elements
Something like:
Pojo p = g.fromJson(json, Pojo.class);
System.out.println(p);
for (Fruits f : p.getParts()) {
System.out.println(f.getId());
System.out.println(f.getName());
}
I have a model that work with multiple JSON responses. However this a response :
items: [
{
kind: "youtube#playlistItem",
etag: ""fpJ9onbY0Rl_LqYLG6rOCJ9h9N8/jqbcTLu8tYm8b1FXGO14gNZrFG4"",
id: "PLUQ7I1jJqKB4lJarGcpWsP62l7iC06IkE2LDE0BxLe18",
That conflict with this one (notice the same id field with different type. The above id is String, the other is a Class) :
items: [
{
kind: "youtube#searchResult",
etag: ""fpJ9onbY0Rl_LqYLG6rOCJ9h9N8/hDIU49vmD5aPhKUN5Yz9gtljG9A"",
id: {
kind: "youtube#playlist",
playlistId: "PLh6xqIvLQJSf3ynKVEc1axUb1dQwvGWfO"
},
I want to read the id field using a single model class.
This is my model Response class :
public class Response {
private ArrayList<Item> items = new ArrayList<Item>();
And this is my model Item class :
public class Item {
private Id id;
//nested class inside Item
public class Id
{
private String id;
private String kind;
private String playlistId;
public String getId() {
return id;
}
public void setId(String id) {
this.id = id;
}
public String getKind() {
return kind;
}
public void setKind(String kind) {
this.kind = kind;
}
public String getPlaylistId() {
return playlistId;
}
public void setPlaylistId(String playlistId) {
this.playlistId = playlistId;
}
}
Notice that the Id class is inside Item class.
This is how i use registerTypeAdapter :
GsonBuilder gsonBuilder = new GsonBuilder();
gsonBuilder.registerTypeAdapter(Response.class,
new JsonDeserializer<Item.Id>() {
#Override
public Item.Id deserialize(JsonElement jsonElement, Type type, JsonDeserializationContext jsonDeserializationContext) throws JsonParseException {
Item.Id result = new Item().new Id();
if(jsonElement.isJsonPrimitive() == false)
{
result.setKind(jsonElement.getAsJsonObject().get("kind").getAsString());
result.setPlaylistId(jsonElement.getAsJsonObject().get("playlistId").getAsString());
//return new Item.Id(jsonElement.getAsJsonObject().get("kind").getAsString(), jsonElement.getAsJsonObject().get("playlistId").getAsString());
return result;
}
else
{
result.setId(jsonElement.getAsString());
//return new Item.Id(jsonElement.getAsString());
return result;
}
}
});
Gson gson = gsonBuilder.create();
Response result = Response.success(
gson.fromJson(json, gsonClass),
HttpHeaderParser.parseCacheHeaders(response));
However the above code throws java.lang.NullPointerException in this line :
if(jsonElement.isJsonPrimitive() == false)
What should i do?
Is this the correct way to use registerTypeAdapter?
Thanks for your time
Your main problem seems to be that you're registering a type adapter for Response class but you're giving a JsonDeserializer that handles Item.Id classes. Either you deserialize a full Response or limit yourself to Item or even Item.Id.
Another problem with deserializing Item.Id (as written in your question) directly is that it's a non-static inner class, which requires an instance of the parent class to be instantiated (as you do with the new Item().new Id()). I think that you would have to deserialize the whole Item manually if you want to keep it as such, frankly I don't see any reason not to make Item.Id static as it would simplify the problem.
Here's my solution with the static version of Item.Id
GsonBuilder builder = new GsonBuilder();
builder.registerTypeAdapter(Item.Id.class, new JsonDeserializer<Item.Id>() {
#Override
public Item.Id deserialize(JsonElement json, Type typeOfT, JsonDeserializationContext context) throws JsonParseException {
Item.Id id = new Item.Id();
if (!json.isJsonPrimitive()) {
JsonObject jsonObject = json.getAsJsonObject();
id.setKind(jsonObject.get("kind").getAsString());
id.setPlaylistId(jsonObject.get("playlistId").getAsString());
} else {
id.setId(json.getAsString());
}
return id;
}
});
And some test snippets that seemed to work for me:
Gson gson = builder.create();
Response response = gson.fromJson("{\n" +
" \"items\": [\n" +
" {\n" +
" \"kind\": \"youtube#playlistItem\",\n" +
" \"etag\": \"fpJ9onbY0Rl_LqYLG6rOCJ9h9N8/jqbcTLu8tYm8b1FXGO14gNZrFG4\",\n" +
" \"id\": \"PLUQ7I1jJqKB4lJarGcpWsP62l7iC06IkE2LDE0BxLe18\"\n" +
" }\n" +
" ]\n" +
"}", Response.class);
Response response2 = gson.fromJson("{\n" +
" \"items\": [\n" +
" {\n" +
" \"kind\": \"youtube#searchResult\",\n" +
" \"etag\": \"fpJ9onbY0Rl_LqYLG6rOCJ9h9N8/hDIU49vmD5aPhKUN5Yz9gtljG9A\",\n" +
" \"id\": {\n" +
" \"kind\": \"youtube#playlist\",\n" +
" \"playlistId\": \"PLh6xqIvLQJSf3ynKVEc1axUb1dQwvGWfO\"\n" +
" }\n" +
" }\n" +
" ]\n" +
"}", Response.class);
If you want to keep Item.Id non-static, I think you need to write a deserializer for Item instead. Also keep in mind that json elements can be absent but the parser should still be able to handle it.
I had just the same problem long time ago, but i was working then with Json.Net, However json concept is (almost) the same so I hope I will succeed help.
I guess it might not work, but why try to not register with the Item class? I mean there is no 'Item.Id' in so it's obious get a null. BUT this: gsonBuilder.registerTypeAdapter(Item.class, likely to fail, becaus you dont parse the Item class explicitly (However it might work, I just never tried it in Gson. But in Json.Net similar way would work proper.)
So, how could you fix that? I'm too lazy to write an paraser but you could look here and read the surt summary summary from here (Search for Using the registerTypeAdapter().
I hope I helped.
I'm relatively new to Java programming and need to parse a complex JSON object across the wire. I've been reading documentation on GSON the past day and Haven't had much luck being able to fully parse this type of structure:
{
'Events' : [{
'name' : 'exp',
'date' : '10-10-2010',
'tags' : ["tag 1", "tag2", "tag3"]
},...more events...],
'Contacts' : [{
'name' : 'John Smith',
'date' : '10-10-2010',
'tags' : ["tag 1", "tag2", "tag3"]
},...more contacts...],
}
I've been able to get it to work similarly to this question but can't figure out how to get that additional array level to work.
The correct way to do it using GSON in the format I'm looking for is:
//somewhere after the web response:
Gson gson = new Gson();
Event[] events = gson.fromJson(webServiceResponse, Event[].class);
//somewhere nested in the class:
static class Event{
String name;
String date;
public String getName()
{
return name;
}
public String getDate()
{
return date;
}
public void setName(String name)
{
this.name = name;
}
public void setDate(String date)
{
this.date = date;
}
}
Java has his own JSON parser: we can use it on Android as well.
Below you can find how you can get all events from your String.
String TAG = "JSON EXAMPLE";
String jsonString = "{\"Events\" : [{\"name\" : \"exp\",\"date\" : \"10-10-2010\",\"tags\" : [\"tag 1\",\"tag 2\",\"tag 3\"]}],\"Contacts\" : [{\"name\" : \"John Smith\",\"date\" : \"10-10-2010\",\"tags\" : [\"tag 1\",\"tag 2\",\"tag 3\"]}]}";
try {
JSONObject jsonObj = new JSONObject(jsonString); // create a json object from a string
JSONArray jsonEvents = jsonObj.getJSONArray("Events"); // get all events as json objects from Events array
for(int i = 0; i < jsonEvents.length(); i++){
JSONObject event = jsonEvents.getJSONObject(i); // create a single event jsonObject
Log.e(TAG, "Event name:" + event.getString("name") + " date: " + event.getString("date"));
JSONArray eventTags = event.getJSONArray("tags");
for(int j = 0; j < eventTags.length(); j++){
Log.e(TAG, "Event tag: " + eventTags.getString(j));
}
}
} catch (JSONException e) {
e.printStackTrace();
}
Be aware: Your JSON Object(from your question) will throw a exception because it is not valid( I'm not sure, but it look like a javascript object). You have to add some quotes to each property(key) and ecape them with \ (\").
This tool is really nice to test if a JSON String is valid or not.