使用Retrofit查询Uber API

Question

I am trying to get products json data from https://api.uber.com/v1/products ( https://developer.uber.com/docs/v1-products ) but I am getting the following error.

E/AndroidRuntime: FATAL EXCEPTION: main
Process: shaurya.uberintegration, PID: 21380
java.lang.NullPointerException: Attempt to read from field 'java.util.Listshaurya.uberintegration.ProductsResponse.products' on a null object reference
at shaurya.uberintegration.Success.onResponse(Success.java:40)
at retrofit.ExecutorCallAdapterFactory$ExecutorCallback$1.run(ExecutorCallAdapterFactory.java:86)
at android.os.Handler.handleCallback(Handler.java:739)
at android.os.Handler.dispatchMessage(Handler.java:95)
at android.os.Looper.loop(Looper.java:135)
at android.app.ActivityThread.main(ActivityThread.java:5294)
at java.lang.reflect.Method.invoke(Native Method)
at java.lang.reflect.Method.invoke(Method.java:372)
at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:904)
at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:699)

Here is the relevant code

RestAPI

public interface RestAPI {
@GET("/v1/products")
Call<ProductsResponse> load(@Header("Authorization") String authToken,
                            @Query("latitude") float latitude,
                            @Query("longitude") float longitude);
}

ProductsResponse

public class ProductsResponse {
public List<ProductsPOJO> products;
}

Code from the Activity

AccessTokenManager accessTokenManager=new AccessTokenManager(this);
    String t= accessTokenManager.getAccessToken().getToken();
    Retrofit retrofit = new Retrofit.Builder()
            .baseUrl("https://api.uber.com")
            .addConverterFactory(GsonConverterFactory.create())
            .build();
    RestAPI restAPI = retrofit.create(RestAPI.class);
    Call<ProductsResponse> call = restAPI.load(t, 28.632328f, 77.216858f);
    call.enqueue(this);
}

@Override
public void onResponse(Response<ProductsResponse> response, Retrofit retrofit) {
    Toast.makeText(getApplicationContext(),response.body().products.get(0).getDescription(),Toast.LENGTH_SHORT)
            .show();

}

@Override
public void onFailure(Throwable t) {

}

Model Class

public class ProductsPOJO {
public String display_name;
public String description;
public ProductsPOJO()
{

}

public String getDisplay_name(){
    return display_name;
}
public String getDescription(){
    return description;
}}

I think it has something to do with authorization and there is some problem with my get request. Kindly point the issue, thanks in advance.

Answer 1

Fixed the problem. Added Bearer to the access token before passing it.

String t= "Bearer "+accessTokenManager.getAccessToken().getToken();