我的问题与此非常相似: Unable to parse Json array using Gson
但我无法从中得到答案。 上面链接的答案:
public static List<MapData> getData(){
Gson gson = new Gson();
String jsonString = "[{\"id\":18,\"city\":\"test\",\"street\":\"test 1\",\"zipcode\":121209,\"state\":\"IL\",\"lat\":32.158138,\"lng\":34.807838},{\"id\":19,\"city\":\"test\",\"street\":\"1\",\"zipcode\":76812,\"state\":\"IL\",\"lat\":32.161041,\"lng\":34.810410}]";
Type type = new TypeToken<List<MapData>>(){}.getType();
return gson.fromJson(jsonString, type);
}
它工作得很好,但我想在泛型类型上使用隐式运算符。见下文:
public static <T> List<T> getData(Class<T> classT){
Gson gson = new Gson();
String jsonString = "[{\"id\":18,\"city\":\"test\",\"street\":\"test 1\",\"zipcode\":121209,\"state\":\"IL\",\"lat\":32.158138,\"lng\":34.807838},{\"id\":19,\"city\":\"test\",\"street\":\"1\",\"zipcode\":76812,\"state\":\"IL\",\"lat\":32.161041,\"lng\":34.810410}]";
Type type = new TypeToken<List<T>>(){}.getType();
return gson.fromJson(jsonString, type);
}
然后我尝试将 Class 参数传递给该方法:
List<MapData> data = getData(MapData.class);
System.out.println(data.get(0).city);
然后出现错误:
java.lang.ClassCastException: com.google.gson.internal.LinkedTreeMap cannot be cast to com.ssc.ctq.nav.util.MapData
谁能告诉我为什么会出现这个错误? TypeToken 类不支持隐式运算符吗?
最佳答案
你可以这样做:
Gson gson = new Gson();
String jsonString = "[{\"id\":18,\"city\":\"test\",\"street\":\"test 1\",\"zipcode\":121209,\"state\":\"IL\",\"lat\":32.158138,\"lng\":34.807838},{\"id\":19,\"city\":\"test\",\"street\":\"1\",\"zipcode\":76812,\"state\":\"IL\",\"lat\":32.161041,\"lng\":34.810410}]";
List<Map> tmpList = gson.fromJson(jsonString);
List<T> resultList = new Arraylist<T>(tmplist.size());
for(Map map:tmpList){
String tmpJson = gson.toJson(map);
resultList.add(gson.fromJson(tmpJson, classT));
}
return resultList;
关于java - GSON解析通用Json数组,我们在Stack Overflow上找到一个类似的问题: https://stackoverflow.com/questions/18712495/