如何在翻新库中使用Gson？

Question

我在Android中使用Retrofit来发送请求并接收响应，但是当我想要转换来自服务器的响应时总是遇到问题Exception：

retrofit.RetrofitError: com.google.gson.JsonSyntaxException: 
               java.lang.IllegalStateException: Expected BEGIN_OBJECT but was STRING

当服务器的响应应该给我电影列表时，我需要将所有这些电影都放在列表中。

Movie （型号类别）：

public class Movie {
    public Movie() {}
    @SerializedName("original_title")
    private String movieTitle;
    @SerializedName("vote_average")
    private String movieVoteAverage;
    @SerializedName("overview")
    private String movieOverview;
    ............  
}

GitMovieApi 类：

public interface GitMovieApi {
    @GET("/3/movie/{movie}")  
    public void getMovie(@Path("movie") String typeMovie,@Query("api_key") String  keyApi, Callback<Movie> response);    
}

RestAdapter 组态：

RestAdapter restAdapter = new RestAdapter.Builder()
                    .setLogLevel(RestAdapter.LogLevel.FULL)
                    .setConverter(new GsonConverter(new GsonBuilder().registerTypeAdapter(Movie.class, new UserDeserializer()).create()))
                    .setEndpoint("http://api.themoviedb.org")
                    .build(); 
                     GitMovieApi git = restAdapter.create(GitMovieApi.class);  
                git.getMovie("popular", "Keyapi", new Callback<Movie>() {
                @Override
                public void success(Movie movie, Response response) {
                    Toast.makeText(getActivity(), "s", Toast.LENGTH_LONG).show();
                }
                @Override
                public void failure(RetrofitError error) {
                    Toast.makeText(getActivity(), error.getMessage(), Toast.LENGTH_LONG).show();
                }
            });

UserDeserializer：

public class UserDeserializer implements JsonDeserializer<Movie> {
        @Override
        public Movie deserialize(JsonElement jsonElement, Type typeOF,
                                 JsonDeserializationContext context)
                throws JsonParseException {
            JsonElement userJson = new JsonParser().parse("results");
            return new Gson().fromJson(userJson, Movie.class);
        }
    }

杰森（回应）：

{
  "page": 1,
  "results": [
    {
      "adult": false,
      "backdrop_path": "/tbhdm8UJAb4ViCTsulYFL3lxMCd.jpg",
      "genre_ids": [
        53,
        28,
        12
      ],
      "id": 76341,
      "original_language": "en",
      "original_title": "Mad Max: Fury Road",
      "overview": "An apocalyptic story set in the furthest.",
      "release_date": "2015-05-15",
      "poster_path": "/kqjL17yufvn9OVLyXYpvtyrFfak.jpg",
      "popularity": 48.399601,
      "title": "Mad Max: Fury Road",
      "video": false,
      "vote_average": 7.6,
      "vote_count": 2114
    },
    {
      "adult": false,
      "backdrop_path": "/sLbXneTErDvS3HIjqRWQJPiZ4Ci.jpg",
      "genre_ids": [
        10751,
        16,
        12,
        35
      ],
      "id": 211672,
      "original_language": "en",
      "original_title": "Minions",
      "overview": "Minions Stuart.",
      "release_date": "2015-06-25",
      "poster_path": "/s5uMY8ooGRZOL0oe4sIvnlTsYQO.jpg",
      "popularity": 31.272707,
      "title": "Minions",
      "video": false,
      "vote_average": 6.8,
      "vote_count": 1206
    },     
],
  "total_pages": 11871,
  "total_results": 237415
}

Answer 1

您甚至不需要在此处制作自定义解串器。

UserDeserializer完全摆脱它，这是不需要的。您的查询返回的是电影列表，因此请对实际读取电影列表的对象进行回调：

public class MovieList {
    @SerializedName("results")
    List<Movie> movieList;
    // you can also add page, total_pages, and total_results here if you want
}

那么您的GitMovieApi课程将是：

public interface GitMovieApi {
    @GET("/3/movie/{movie}")  
    public void getMovie(@Path("movie") String typeMovie,
                @Query("api_key") String keyApi,
                Callback<MovieList> response);    
}

您的RestAdapter：

RestAdapter restAdapter = new RestAdapter.Builder()
                .setLogLevel(RestAdapter.LogLevel.FULL)
                .setConverter(new GsonConverter(new GsonBuilder()).create()))
                .setEndpoint("http://api.themoviedb.org")
                .build(); 
                 GitMovieApi git = restAdapter.create(GitMovieApi.class);

这个问题是 不是 你写的Deserializer不正确的（虽然，你有，但没关系，因为你不需要它，JsonParser是 不是
你如何做到这一点），但是默认的反序列化行为，应该只是罚款你。使用上面的代码，它将正常工作。