为什么在使用改造时我的类中的init块没有被触发？

Question

所以从服务器我会得到这样的JSON:

{
    "success": "1",
    "data": [
        {
            "id": 1,
            "title": "1",
            "url": "5",
            "image": "resources/assets/images/banner_images/1548316546.mitra lakuin.png",
            "type": "category"
        },
        {
            "id": 2,
            "title": "2",
            "url": "5",
            "image": "resources/assets/images/banner_images/1548316605.mobile banner_-02 (1).png",
            "type": "category"
        },
        {
            "id": 4,
            "title": "4",
            "url": "5",
            "image": "resources/assets/images/banner_images/1547010221.gratis ongkir.png",
            "type": "category"
        },
        {
            "id": 5,
            "title": "Customer",
            "url": "5",
            "image": "resources/assets/images/banner_images/1548316659.customer service.png",
            "type": "category"
        }
    ],
    "message": "Banners are returned successfull."
}

我创建了2个类,以便将该JSON转换为Banner对象.

// 1.
class BannerData(val message : String, val success : String, val data : List<Banner>) {}

// 2.

class Banner(id: Int, imageURL: String) {

    @SerializedName("image")
    var imageURL : String
    val id : Int

    init {
        Log.i("testX","triggered")

        this.id = id

        // The code below is used to add percent encoding to URL from server

        val unformattedFullPath = "${Endpoint.lakuin}/$imageURL"
        val formattedFullPath = URLConverterService.addingPercentEncoding(unformattedFullPath)
        this.imageURL = formattedFullPath

    }

}

改造界面是这样的:

    @GET("/app/getbanners")
    fun getBanners(): Call<BannerData>

界面构建器是这样的:

object RetrofitHandler {

    private val loggingInterceptor = HttpLoggingInterceptor().setLevel(HttpLoggingInterceptor.Level.BODY)

    private val okHttpClient = OkHttpClient.Builder()
        .callTimeout(7,TimeUnit.SECONDS)
        .addInterceptor(loggingInterceptor)
        .build()

    private var retrofit = Retrofit.Builder()
        .baseUrl(Endpoint.lakuin) // default is set to lakuinAPI
        .addConverterFactory(GsonConverterFactory.create())
        .client(okHttpClient)
        .build()


    fun <T> getInstance(APIType: Class<T>) : T {
        // baseURL should be change later, if there is more than one API, ex: GoogleMapAPI, LakuinAPI etc
        return retrofit.create(APIType)
    }

}

我的问题是......

从上面的JSON可以看出,图像URL不完整,我想转换imageURL

来自:"resources/blablabla.png"

将:" http://xxxx.com/resources/blablabla.png "

我尝试在Banner类中的init块内转换它.

但是.....似乎类中的init块Banner永远不会被触发,我尝试记录它但我在logcat中找不到,那Log.i("testX","triggered")从未在logcat中显示

我实际上可以创建Banner对象,但imageURL与JSON完全相同,这意味着永远不会触发init块

那么这里出了什么问题？

Answer 1

如果你设置改造使用Gson库作为序列化/反序列化对象的库addConverterFactory(GsonConverterFactory.create(gson)),Gson默认情况下不使用构造函数或init函数,instantiate an object and set its fields via reflection所以我猜你的init块只是跳过,看看Gson库,了解你是否可以配置为不跳过init功能.