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我有一個Retrofit接口，我與RxJava結合。我所有的翻新電話都會返回Observable。那些「SomePojo」類，我使用Schema2Pojo網站在線生成它們。Gson + AutoValue錯誤，試圖實現自己的解串器
我做以下API調用時的一個問題： https://developers.themoviedb.org/3/search/2Y9y2LReFZdHFHbFA
正如你所看到的，這是兩種不同類型的對象的數組，我所謂的「媒體」和「信用」。
@AutoValue
public abstract class Media implements Parcelable {
@SerializedName(value = "title", alternate = {"name"})
public abstract String title();
@Nullable
@SerializedName("vote_average")
public abstract String voteAverage();
@Nullable
@SerializedName("backdrop_path")
public abstract String backdropPath();
@Nullable
public abstract String adult();
public abstract String id();
@Nullable
public abstract String overview();
@Nullable
@SerializedName("original_language")
public abstract String originalLanguage();
@Nullable
@SerializedName("genre_ids")
public abstract List<String> genreIds();
@Nullable
@SerializedName(value = "release_date", alternate = {"first_air_date"})
public abstract String releaseDate();
@Nullable
@SerializedName(value = "original_title", alternate = {"original_name"})
public abstract String originalTitle();
@Nullable
@SerializedName("vote_count")
public abstract String voteCount();
@Nullable
@SerializedName("poster_path")
public abstract String posterPath();
@Nullable
public abstract String video();
@Nullable
@SerializedName("media_type")
public abstract String mediaType();
@Nullable
public abstract String popularity();
@Nullable
@SerializedName("origin_country")
public abstract List<String> originalCountry();
public static Media create(String title, String voteAverage, String backdropPath,
String adult, String id, String overview, String originalLanguage,
List<String> genreIds, String releaseDate, String originalTitle,
String voteCount, String posterPath, String video, String mediaType,
String popularity, List<String> originalCountry) {
return new AutoValue_Media(title, voteAverage, backdropPath, adult, id, overview,
originalLanguage, genreIds, releaseDate, originalTitle, voteCount, posterPath,
video, mediaType, popularity, originalCountry);
}
public static TypeAdapter<Media> typeAdapter(Gson gson) {
return new AutoValue_Media.GsonTypeAdapter(gson);
}
}
和：我生成使用谷歌的autovalue如下這兩個類
@AutoValue
public abstract class Credit implements Parcelable {
public abstract String id();
@SerializedName("credit_id")
public abstract String creditId();
@Nullable
public abstract String department();
public abstract String name();
@Nullable
@SerializedName(value = "job", alternate = {"character"})
public abstract String job();
@Nullable
@SerializedName("profile_path")
public abstract String profilePath();
@Nullable
public abstract String order();
@Nullable
@SerializedName("cast_id")
public abstract String castId();
public static Credit create(String id, String creditId, String department, String name, String job,
String profilePath, String order, String castId) {
return new AutoValue_Credit(id, creditId, department, name, job, profilePath, order, castId);
}
public static TypeAdapter<Credit> typeAdapter(Gson gson) {
return new AutoValue_Credit.GsonTypeAdapter(gson);
}
}
要解決由陣列兩種不同類型的對象所產生的問題，我做了這個調用POJO回報實現自己的JsonDeserializer：
public class MediaListPojo {
@SerializedName("results")
private List<Media> movies;
private List<Credit> credits;
private Dates dates;
private String page;
private String total_pages;
private String total_results;
public List<Media> getMedia() {
return movies;
}
public void setMovies(List<Media> movies) {
this.movies = movies;
}
public List<Credit> getCredits() {return credits;}
public void setCredits(List<Credit> credits) {this.credits = credits;}
public Dates getDates() {
return dates;
}
public void setDates(Dates dates) {
this.dates = dates;
}
public String getPage() {
return page;
}
public void setPage(String page) {
this.page = page;
}
public String getTotal_pages() {
return total_pages;
}
public void setTotal_pages(String total_pages) {
this.total_pages = total_pages;
}
public String getTotal_results() {
return total_results;
}
public void setTotal_results(String total_results) {
this.total_results = total_results;
}
@Override
public String toString() {
return "MediaListPojo{" +
"movies=" + movies +
", credits=" + credits +
", dates=" + dates +
", page='" + page + '\'' +
", total_pages='" + total_pages + '\'' +
", total_results='" + total_results + '\'' +
'}';
}
public static class MediaListPojoDeserializer implements JsonDeserializer<MediaListPojo> {
@Override
public MediaListPojo deserialize(JsonElement json, Type typeOfT,
JsonDeserializationContext context) throws JsonParseException {
MediaListPojo mediaListPojo = new Gson().fromJson(json, MediaListPojo.class);
JsonObject jsonObject = json.getAsJsonObject();
if (jsonObject.has("results")) {
JsonArray jsonArray = jsonObject.getAsJsonArray("results");
List<Credit> credits = new ArrayList<>();
Credit credit;
for (JsonElement element : jsonArray) {
JsonObject current = element.getAsJsonObject();
if (current.get("media_type").getAsString().equals("person")) {
credit = new Gson().fromJson(current, Credit.class);
credits.add(credit);
}
}
mediaListPojo.setCredits(credits);
}
return mediaListPojo;
}
}
}
此JSON解串器背後的主要思想是：「使用默認類型的適配器這個類，然後設置信貸對象全光照克這種JsonDeserializer」
然而，出於某種原因，我得到以下錯誤，而反序列化：
了java.lang.RuntimeException：無法用無參數 ... 所致調用公共媒體（）： java.lang.InstantiationException：不能實例化抽象類媒體 在java.lang.reflect.Constructor.newInstance（本地方法）
它不應嘗試實例化抽象超類，但使用AutoValue生成的類型適配器。
這是我建立了我的改裝實例：
class Creator {
public static MovieService newMovieService() {
Gson gson = new GsonBuilder()
.registerTypeAdapterFactory(new AutoValueGson_MyAdapterFactory())
.registerTypeAdapter(MediaListPojo.class, new MediaListPojo.MediaListPojoDeserializer())
.setDateFormat("yyyy-MM-dd'T'HH:mm:ss.SSS'Z'")
.create();
OkHttpClient client = new OkHttpClient.Builder()
.addInterceptor(NetworkUtil.makeQueryInterceptor("api_key", BuildConfig.MY_API_KEY))
.build();
Retrofit retrofit = new Retrofit.Builder()
.client(client)
.baseUrl(MovieService.ENDPOINT)
.addConverterFactory(GsonConverterFactory.create(gson))
.addCallAdapterFactory(RxJavaCallAdapterFactory.create())
.build();
return retrofit.create(MovieService.class);
你能幫助我理解我做錯了什麼？
錯過了也......有時我們是馬虎不得。 – box