Migrate Web Service API from Java to Kotlin

interface

public interface ArticlesServiceApi {
    @GET("demo-articles.json")
    LiveData<ApiResponse<List<Article>>> getArticles();
}

// 1
interface ArticlesServiceApi {
    @get:GET("demo-articles.json")
    val articles: LiveData<ApiResponse<List<Article>>>
}

// 2
interface ArticlesServiceApi {
    @GET("demo-articles.json")
    fun getArticles(): LiveData<ApiResponse<List<Article>>>
}

Expected BEGIN_ARRAY but was BEGIN_OBJECT at line 1 column 2 path $

class WebServiceGenerator 工作正常，但自动转成 Kotlin 代码后就出现了这个问题，问题出在这个方法，目前不清楚原因 TODO，所以暂时没有把这个Java类转成Kotlin：

@Provides
@Singleton
fun provideGson(articlesDeserializer: ArticlesDeserializer,
                articleDeserializer: ArticleDeserializer): Gson {
    val articleType = object : TypeToken<List<Article>>() {}.type
    return GsonBuilder()
            .setLenient()
            .registerTypeAdapter(Article::class.java, articleDeserializer)
            .registerTypeAdapter(articleType, articlesDeserializer)
            .create()
}

The spread operator (*) is used to pass an array when vararg arguments are expected

Java codes:

@Override
protected void saveCallResult(@NonNull List<Article> articles) {
    mArticlesDao.bulkInsert(articles.toArray(new Article[articles.size()]));
}

Kotlin codes:

override fun saveCallResult(articles: List<Article>) {
    mArticlesDao.bulkInsert(*articles.toTypedArray())
}

2018-08-27 Weiyi Li