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Retrofit - Send request body as array or number

I'm using Retrofit 2 and I need to send request body. The problem is somehow the value is converted to string. On the example below, you can see that items and totalPrice which should be array and number respectively are converted to string.
{ cashierId: 'fff7079c-3fc2-453e-99eb-287521feee63',
items: '[{"amount":3,"id":"602a79e3-b4c1-4161-a082-92202f92d1d6","name":"Play Station Portable","price":1500000.0}]',
paymentMethod: 'Debt',
totalPrice: '4500000.0' }
The desired request body is
{ cashierId: 'fff7079c-3fc2-453e-99eb-287521feee63',
items: [{"amount":3,"id":"602a79e3-b4c1-4161-a082-92202f92d1d6","name":"Play Station Portable","price":1500000.0}],
paymentMethod: 'Debt',
totalPrice: 4500000.0 }
Here's the service
#POST("api/sales")
#FormUrlEncoded
Call<Sale> createSale(
#FieldMap Map<String, Object> fields
);
And this is how I call createSale
Map<String, Object> fields = new HashMap<>();
fields.put("cashierId", UUID.fromString("fff7079c-3fc2-453e-99eb-287521feeaaa"));
fields.put("totalPrice", totalPrice);
fields.put("paymentMethod", paymentMethod);
fields.put("items", jsonArray);
Call<Sale> call = retailService.createSale(fields);
Is it possible to send those values as number and array, not as string?

The conversion most certainly happens because you are using #FormUrlEncoded.
According to the documentation:
Field names and values will be UTF-8 encoded before being URI-encoded in accordance to RFC-3986.
A solution would be to use a model class instead of a Map. I see you already have a Sale class. If it looks like something like this:
public class Sale {
String cashierId;
int totalPrice;
String paymentMethod;
ArrayList<SomeObject> items;
}
you can simply do like this:
// in service
#POST("api/sales")
Call<Sale> createSale(#Body Sale sale);
// when doing the call
Sale sale = new Sale();
// set everything in your object
// then
Call<Sale> call = retailService.createSale(sale);

Add an array as request parameter with Retrofit 2

I'm looking for way to add an int array (e.g [0,1,3,5]) as parameter in a GET request with retrofit 2. Then, the generated url should be like this : http://server/service?array=[0,1,3,5]
How to do this ?

Just add it as a query param
#GET("http://server/service")
Observable<Void> getSomething(#Query("array") List<Integer> array);
You can also use int[], or Integer... as a last param;

You need to name your query param with an array syntax like so:
#GET("http://server/service")
Observable<Void> getSomething(#Query("array[]") List<Integer> array);
The syntax itself will vary by the backend technology being used, however not including the brackets "[]" will normally be interpreted as a single value.
For example, using array=1&array=2 will generally be interpreted by backends as only array=1 or array=2 instead of array=[1,2].

I have finally founded a solution by using Arrays.toString(int []) method and by removing spaces in this result because Arrays.toString return "[0, 1, 3, 5]". And my request method looks like this
#GET("http://server/service")
Observable<Void> getSomething(#Query("array") String array);

I faced a similar problem and had to do a couple of things to reach the acceptable form (as asked in the question).
Converted an ArrayList to String
arrayList.toString().replace(" ", "")
In RetroFit method, I changed the Query param which accepts the ArrayList above to as follows:
#Query(value = "cities", encoded = true)
This ensures that the brackets and commas are not URL encoded.

Using toString didn't work for me.
Instead, TextUtils.join(",", ids) does the trick.
Don't forget to mark the Query with encoded = true.

Well this did the trick for me
Step 1 :
In StateServce.kt
#GET("states/v1")
fun getStatesByCoordinates(#Query("coordinates", encoded = true) coordinates: String) : Call<ApiResponse<List<State>>>
Step 2
While calling from repository
val mCoordinate : List<Double> = [22.333, 22.22]
mStateService?.getStatesByCoordinates(mCoordinate.toString().replace(" ", ""))!!

Use Iterable to encapsulate the integer list, or use a two-dimensional integer array.
How to define:
public interface ServerService {
#GET("service")
Call<Result> method1(#Query("array") Iterable<List<Integer>> array);
#GET("service")
Call<Result> method2(#Query("array") Integer[][] array);
}
How to use:
Retrofit retrofit = new Retrofit.Builder()
.baseUrl("http://server/")
.addConverterFactory(GsonConverterFactory.create())
.build();
ServerService service = retrofit.create(ServerService.class);
// Use the first method.
List<Integer> data1 = Arrays.asList(0,1,3,5);
Iterable array1 = Arrays.asList(data1);
Call<Result> method1Call = service.method1(array1);
// Use the second method.
Integer[] data2 = new Integer[]{0,1,3,5};
Integer[][] array2 = new Integer[][]{data2};
Call<Result> method2Call = service.method2(array2);
// Execute enqueue() or execute() of method1Call or method2Call.
Please refer to the code ParameterHandler.java of Retrofit2 for the reason why the way can solve the problem.

You can pass the value as below
In Repository
getApiResponse(arrayOf(0,1,3,5).contentToString())` In Kotlin.
#GET("http://server/service")
suspend fun getApiResponse(#Query("array") array: String): Response
It will work.

How to structure a Map from Json that has duplicate keys

Ok so I have this piece of JSON that I want to parse with Gson. I would like the Strings to be the values and the longs to be the keys.
{"completed_questions":[["String",12345],...]}
The issue is the data type, when I try a Map<String, Long> it parses everything but gives me an error because of the duplicate String keys.
I tried to reverse it thinking Gson would know to switch them around but when I tried Map<Long, String> I got an error about not being able to parse my Strings as Longs.
To get it to work I created a swap map class that takes the Key and Value types and swaps them like so public class SwapMap<K, V> implements Map<K, V> however translating the swapped map actions like put/get/remove seem to be pretty difficult to make work.
What's the best way to parse this with Gson even though the strings aren't unique? (But the numbers are)

JSON doesn't allow identical keys on the same level in a json object. It seems like you are trying to map a json array to a java map.
Based on the following data structure, you would need a list if you want to use the default conversion provided by Gson.
{
"completed_questions": [
[
"String",
12345
],
[
"String",
12345
]
]
}
Here is a quick implementation:
private static void mapToObject() {
String json = "{\"completed_questions\":[[\"String\",12345],[\"String\",123456]]}";
Gson gson = new Gson();
CompletedQuestions questions = gson.fromJson(json, CompletedQuestions.class);
for (List<String> arr : questions.getCompleted_questions()) {
for (String val : arr) {
System.out.print(val + " ");
}
System.out.println();
}
}
public static class CompletedQuestions {
List<List<String>> completed_questions;
public List<List<String>> getCompleted_questions() {
return completed_questions;
}
}
This outputs:
String 12345
String 123456
The thing to note is that I am using a list for mapping purposes which closely resembles the data model provided.
This will require you to do the conversion to long yourself. But the way that json string looks. It seems like you would need to operate on the indices. If you have control over the json structure, I would recommending creating a better model. Other wise you can do something like list.get(0) -> your key list.get(1) -> your value which is the long on the inner list.

So what I did is just made a custom Gson Deserializer that mapped these values to a LongSparseArray<String>, which is the best way to go about it.
This is the relevant parts of the Deserializer:
for (JsonElement array : jsonObject.get("my_key").getAsJsonArray()) {
if (array.getAsJsonArray().size() == 2) {
String value = array.getAsJsonArray().get(VALUE).getAsString();
long key = array.getAsJsonArray().get(KEY).getAsLong();
progress.completedActivities.put(key, value);
}
}
Then I just added it to my Gson creator like so:
#Provides #Singleton Gson provideGson() {
return new GsonBuilder()
.registerTypeAdapter(MyClass.class, new MyClass())
.create();
}

How to send Arrays / Lists with Retrofit

I need to send a list / an array of Integer values with Retrofit to the server (via POST)
I do it this way:
#FormUrlEncoded
#POST("/profile/searchProfile")
Call<ResponseBody> postSearchProfile(
#Field("age") List<Integer> age
};
and send it like this:
ArrayList<Integer> ages = new ArrayList<>();
ages.add(20);
ages.add(30);
ISearchProfilePost iSearchProfile = gsonServerAPIRetrofit.create(ISearchProfilePost.class);
Call<ResponseBody> call = iSearchProfile.postSearchProfile(
ages
);
The problem is, the values reach the server not comma separated. So the values there are like age: 2030 instead of age: 20, 30.
I was reading (e.g. here https://stackoverflow.com/a/37254442/1565635) that some had success by writing the parameter with [] like an array but that leads only to parameters called age[] : 2030.
I also tried using Arrays as well as Lists with Strings. Same problem. Everything comes directly in one entry.
So what can I do?

To send as an Object
This is your ISearchProfilePost.class
#FormUrlEncoded
#POST("/profile/searchProfile")
Call<ResponseBody> postSearchProfile(#Body ArrayListAge ages);
Here you will enter the post data in pojo class
public class ArrayListAge{
#SerializedName("age")
#Expose
private ArrayList<String> ages;
public ArrayListAge(ArrayList<String> ages) {
this.ages=ages;
}
}
Your retrofit call class
ArrayList<Integer> ages = new ArrayList<>();
ages.add(20);
ages.add(30);
ArrayListAge arrayListAge = new ArrayListAge(ages);
ISearchProfilePost iSearchProfile = gsonServerAPIRetrofit.create(ISearchProfilePost.class);
Call<ResponseBody> call = iSearchProfile.postSearchProfile(arrayListAge);
To send as an Array List check this link https://github.com/square/retrofit/issues/1064
You forget to add age[]
#FormUrlEncoded
#POST("/profile/searchProfile")
Call<ResponseBody> postSearchProfile(
#Field("age[]") List<Integer> age
};

Retrofit can do this now at least I tested with this -> implementation 'com.squareup.retrofit2:retrofit:2.1.0'
For example
#FormUrlEncoded
#POST("index.php?action=item")
Call<Reply> updateStartManyItem(#Header("Authorization") String auth_token, #Field("items[]") List<Integer> items, #Field("method") String method);
This is the piece we are looking at.
#Field("items[]") List<Integer> items

Gson to convert JSON to Object that contain HastMap of Objects?

I have a problem that I have no idea about this, can anyone help me:
Ex we have a json:
{
"status":"0",
"result": {
"object1": {
"name":"name1",
"age":"21"
},
"object2": {
"event":"new year",
"date":"date"
},
"object1_1": {
"name":"name2",
"age":"22"
},
"object2_1": {
"event":"birthday",
"date":"date"
}
}
}

you can try convert to object by using jackson json.
http://jackson.codehaus.org/

If you want to deserialize this json to an object that contains a Map (and the map contains litteral values and other maps). Assuming you have a bean similar to :
class MyBean {
int status;
Map<String, Object> result;
}
MyBean myBean = new Gson().fromJson(jsonString, MyBean.class);
It should work with no modification. Note that if the type of status is not a number I'm not sure Gson does the conversion as in the json string the value is quoted, same thing applies to your "age" property.
You can also have a look at Genson library http://code.google.com/p/genson/ it has most Gson features, other ones that no other library provide and has better performances. Have a look at the wiki http://code.google.com/p/genson/wiki/GettingStarted.
EDIT
Are the names really things like object1_1, object2_1 etc? When looking at the structure I imagine that object1 goes with object2 and so long. If you use gson you can write a custom TypeAdapter http://google-gson.googlecode.com/svn/trunk/gson/docs/javadocs/com/google/gson/TypeAdapter.html.
So you can create a root object similar to
class Response {
int status;
List<MyObject> result;
}
class MyObject {
String name;
int age;
String event;
String date;
}
In the read method of your TypeAdapter you should compose instances of MyObject based on the keys (object1 with object2, object1_1 with object2_1...) or take a similar approach.
If you want more details on how to do that you can also ask on Gson google group.