不幸的是,我从JSON文件中提取的节点具有相同的变量名,但可以随机具有两种不同的数据类型。当我拨打网络电话(使用gson)时,出现错误:
com.google.gson.JsonSyntaxException: java.lang.IllegalStateException: Expected a BEGIN_ARRAY but was int at line 1 column 5344 path $[1].medium
JSON看起来像
{
"title": "Live JSON generator",
"url": google.com,
"medium": ["chicken", "radio", "room"]
}
//However sometimes medium can be:
"medium": 259
我的序列化类如下:
data class SearchItem(
@SerializedName("title") var title: String,
@SerializedName("url") var urlStr: String,
@SerializedName("medium") val medium: List<String>? = null
) : Serializable {}
我进行网络通话的方式是这样的:
private val api: P1Api
fun onItemClicked(searchItem: SearchItem) {
api.getCollections { response, error ->
response.toString()
val searchItems: List<SearchItem> = Util.gson?.fromJson<List<SearchItem>>(
response.get("results").toString()
, object : TypeToken<List<SearchItem>>() {}.type)?.toList()!!
...
doStuffWithSearchItems(searchItems)
}
我如何处理“中号”可以是字符串数组还是整数的两种情况?
您可以为这种情况编写自定义的JsonDeserializer:
class SearchItemCustomDeserializer: JsonDeserializer<SearchItem> {
override fun deserialize(json: JsonElement, typeOfT: Type, context: JsonDeserializationContext): SearchItem {
val obj = json.asJsonObject
val title = obj.get("title").asString
val url = obj.get("url").asString
val mediumProp = obj.get("medium")
val medium = if(mediumProp.isJsonArray) {
mediumProp.asJsonArray.map { it.asString }
} else {
listOf(mediumProp.asString)
}
return SearchItem(
title = title,
urlStr = url,
medium = medium
)
}
}
使用此类,您可以“手动”将json反序列化为对象。对于中等属性,我们检查此数组或具有函数mediumProp.isJsonArray
的简单json原语。如果答案是肯定的,则将字段反序列化为字符串的json数组mediumProp.asJsonArray.map { it.asString }
否则将字段反序列化为字符串。
然后,我们使用方法registerTypeAdapter
在GsonBuilder上注册自定义SearchItemCustomDeserializer,>
val gson = GsonBuilder() .registerTypeAdapter(SearchItem::class.java, SearchItemCustomDeserializer()) .create()
然后,您可以使用此gson实例反序列化您的对象